Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Pleasure boats, Sports, Race, Power and Leisure Boats: => Topic started by: Biscuit on October 19, 2008, 10:25:08 pm
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Hi all not been on here for a while, just wondered what you all think of the Venom King of Shaves RTR? I know it looks a little slow but I think it may only be the exhaust, its right up my street as its so scale :-) would you think a change of engine might help? if it went as fast as my Shockwave I would be happy. The only problem would be the radio which I would throw away and I would have to fit a clutch, so lets get this right £625, throw away the radio, change the motor and pipe, add a clutch, Hmm what was I thinking? it would be so nice if you could just buy the hull finished and painted, anyway you got any thoughts on this?
Cheers
Steve
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Right then.
Would be ok, but the pipe, radio box, steering servo and prop will all be throwaways. Not sure if it an actual Zen, or a copy, but looks ok. The rails will most definately need beefing up, and the fuel tank will need replacing with a central one. A plastic rudder strut on a 26cc gaser?? ermm no... The radio will probably need replacing too, and those engine mounts don't look all that good.
Which does actually leave you paying £625 for a hull and an engine...
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http://www.shopatron.com/product/part_number=VEN1807/745.0
http://uk.youtube.com/watch?v=ZTUaB6wdBgQ
http://uk.youtube.com/watch?v=2j90bWIPySE
(http://www.shopatron.com/img/product_images/745/743651d30e66b8eeee41fab5a084bc5c.jpg)
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Yeah thanks guys, I thought it would be like any other ready to run with cheap radio, did not know it had plastic hardware, oh well it was just a thought, been looking for a scale boat for a while now.
Steve.
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It would be much cheaper to get a Makara running, and they are scale models (ish) of an Apache, so you could do it up scale wise a bit
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Nah, just like the look of the King of Shaves, shame its so slow. <:(
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This one seems to be doing OK! - http://uk.youtube.com/watch?v=6m6APekIkgs
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Wonder why you can't hear the chase boat engine?? Perhaps it has an electric outboard on it - that's why it's faster {-) {-) {-)
Danny
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May I point out that that boat has a max speed of 30ish mph, the chase boat probably has a max speed of 20 ish, and that hull with the right engine and pipe probably has the potential to do 50 - 60 odd mph.
Pat from our club runs a simalar hull with an A90 in it and gets around 70 on our small lake
It also doesn't appear to be balanced right, see the nose dives off waves?
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The Venom King of Shaves is a "safe" of the self boat that most people could buy and run.... which is fine if that's what you want.
Buy it, charge and fuel it up have a run, don't clean it down, put it in the garage for 3 weeks, get it out charge it up, fuel, etc, etc.
Supped up maximum power OMRA boats are something else..... 'horses for courses!'
I sound like I'm try to sell you one of the stupid things! :D
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OMRA boats are mostly hardly 'souped' up, quite a lot of the boats in D class for example are using standard Zenoah G260's, quite a lot of the other classes are standard engines, and some are buggy motors with colling jackets around the heads.
And it is still cheaper to build an OMRA boat from scratch than to buy a King Of Shaves.
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Give us a costing Andy, I've never built a petrol OMRA boat...... {:-{
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I'll do my best....
I'll point out before I begin, I personally would not deal with Prestwich Models, all parts would come from Bonzi.
Nimrif models - Makara - £125 I think, I stand to be corrected as there are no prices on his site...
Bonzi Sports - Zenoah G260pum with mounts and collets - $279.95 - £170.74 at time of writing
Prestwich Models - Tuned Pipe - £69.50
Stinger assembly with stuff tube and flexi - £47.90
Rudder - £26.95
Prop - various choices specific to engine, lake etc, but all are around £20
Radio box - £24.95
FlexHex - 12.95
Manifold - £25
LMS (local model shop) - Ripmax Fuel tank, one of the big yellow jobs - £8.35
Cost so far - £530.94
You will also need a controller (obviously) for which a Spektum DX5e is excellent, so thats an extra £60
Other accessories such as a couple of bits of Marine Grade ply to make the engine rails, some rx aerial tubes, £5.79 a can for paint and primer from Halfords, some Tygon petrol tubing, an NGK Iridium spark plug, and an Rx battery.
So then, to fit out a Makara would be £ 590.94, plus the extra bits above, and also for radio boxes use a metal sandwich tin with some self adhesive neoprene inside, which are from camping shops for £8. To use Bonzi from america is a lot cheaper than Prestwich, so we shall say for the purposes of this if you spend over £600 you have gone seriously wrong somewhere
Makara - £600 absolute maximum
King Of Shaves - £625, then all of the above to replace the simply awful bits already installed.
It would be far better as a first boat to fit out an AA / A class boat, which will be a considerable amount cheaper than this, but we like the expensive stuff don't we?
Also, as a personal thing, If I had the money to do this and not just the knowhow, I would fit a Bonzi BZX4 engine, 5.5HP@16,800RPM equals one veryveryvery fast boat!
http://bonzisports.com/ (http://bonzisports.com/)
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Yeah but I' have build all that! ok2
King of Shaves is nice but a whole heap a money! {:-{
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Hi Martin
Model boating is for me not only the running and repairing the boat, It is spending time building it yourself and learning from your mistakes.
I have almost as much fun putting a boat together as i do racing it.
There are a few ebay sellers which will sell you a stock 26cc Zen for less then £150.00 inc P&P. I can't remember there web site but one is based in Singapore and one in Hong Kong. I have in the passed got parts from both dealers with no probs at all. I have just got parts to rebuild my Silk engine from O'Neil Bros USA. They where spot on. A barrel, piston, piston pin, clip's, bearings, gaskets, spark plug was all sent to me in very quick time and a bargin price, and whats more there was NO P&P added to there web list price. Very good service me thinks.
You do have to be carefull with the tuned pipes. OMRA have a sound limit to work to. There are allot of pipes which are far to loud to run over here. Many of these tuned pipes are fitted to RTR type boats found on ebay. You should change them to a quite pipe as you will upset the lake owners and we will all have nowhere to run our IC boats if that happens. A good tuned pipe will cost you around £100. Add that on to the cost of your RTR boat and the price starts looking nearer £750.
Andy is about right with his prices for the Makara set up. Mine has set me backabout £600 this year. Bear in mind I got a new engine + i learned from my mistakes.
O well best get off. DON'T let any one having a go at a OMRA D class boat as many parts can be got second hand from other like mined boaters Which all helps to keep the cost down when you are starting out.
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Bill raised a very good point there, and one that I didn't want to raise in my posting because second hand and ebay parts vary in price massively.
Provided that you have a good source of parts, someone who has looked after them well, you can considerably cut the cost of building the boats.
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All I am saying is that I would like a scale boat that is fast as well, the King of Shaves looks so nice, there is a lot of Zen powered boats on this site but look nothing like any boat I know, there must be someone out there that can do a painted a stickered up scale hull that just needs to be fitted out ??
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Hi
Tbh it did well over the 2 mile lake %) the real king of shaves woulda only lasted 1 mile {-)
Looks way to slow though n as said before needs some more weight up the back :)
All the best
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WOT NO VIDEO OF IT'S 1ST OUTTING????
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I have heard that Venom is having issues with the "hand laid" fiberglass hulls.
Something to the effect that the hulls are hand laid, but maybe not by a professional...
Well maybe by a professional, as the person gets paid for the work, but maybe not quality work.
The report was that the mounting rails and engine mounts were poorly done, and the hull had to be replaced.
Radio didn't work out of the box, and was also replaced.
These guys just kill me. Back in May, we had a customer purchase their new gasoline-powered Segad R/C boat.
From day one, he had radio issues (it kept re-programming itself), paint issues (they informed him in a piece of paper in the box the paint was a 'prototype') with runs and thin coverage, poorly fiberglassed motor mount and fuel tank rails.
After several weeks of trying to contact Venom's Customer Service about these issues, I was told by someone called Jason (who said he was the head CS guy) and explained the issues and gave him the customer's phone number. He said he'd call him 'right away'.
Two days later he still hadn't called the customer so I called again and left (yet another) voice mail. Jason called me, apologized and called the customer.
The customer called me to thank me for getting them to call him and that they were sending him a new radio and parts to fix the broken rails.
Two weeks ago, the radio issues returned which caused the boat to crash hard, breaking loose the previous repairs and splitting the hull. So, another series of calls to Venom (and Jason) and the customer calls me to say he's bringing the boat back for a refund or exchange.
Second report that the new radio failed and the boat crashed.... Now that could be, but
I don't know who was running the boat, and what his experience level was.... Could be that
the owner just turned the wrong left, and hit a wall on the right..
If you purchase one, maybe pick it up at a reputable shop that will let you open the box before you buy.
:-)
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Hi all not been on here for a while, just wondered what you all think of the Venom King of Shaves RTR? I know it looks a little slow but I think it may only be the exhaust, its right up my street as its so scale :-) would you think a change of engine might help? if it went as fast as my Shockwave I would be happy. The only problem would be the radio which I would throw away and I would have to fit a clutch, so lets get this right £625, throw away the radio, change the motor and pipe, add a clutch, Hmm what was I thinking? it would be so nice if you could just buy the hull finished and painted, anyway you got any thoughts on this?
Cheers
Steve
Ready to run and fast are words that dont mix usually,far better find a hull you like and build it yourself.Does it have to be a cat? how about a roundnose hydro or a vee?.Im building a plug for a hydro as we speak 50+ with a stock zenoah and 65+ with a full mod is more than possible, in case your interested pm me.
Mart
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Thanks Mart but I dont really want to build one from scratch, like I said would like to buy a hull painted with all the hardwear and just drop in my motor and radio, seen this on the bay but its just the hull
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=300271696194
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Vern Kilmer is the guy,pretty looking boats he builds but you might want to research him a bit b4 you buy,anyway just remember anything over 46" you pay much more import duty and last quote i got for shipping my boats to usa was $260 us then you have duty on topso be aware of that before you order.Same goes for the chinese ones cheap quotes they give you for shipping but import duty is high.
Mart
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This one seems to be doing OK! - http://uk.youtube.com/watch?v=6m6APekIkgs
Wonder if that boat in the video had the 4.5hp KWA engine in it that Venom are now advertising in the current (U.S.) Radio Control Boat Modeler Mag?
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Funny thing is if you look at that new venom motor its actually a sikk motor with a different sticker on the starter %).
Mart
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Had it confirmed it is a cy motor they call theres a KWA whereas the other importers call theres a sikk ,same motor built at chung yang in China.He reckons its hit 63 mph with a stock KWA motor ,seems hopefull but you never know.Love to see the proof though ok2.
Mart
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A better boat? - :-)) http://uk.youtube.com/watch?v=K0C6_mfVwgs
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Martin thats deff a better boat its my mate Waynes boat its a cto3 from MHZ with twin counter rotating moddified zenoahs it was orriginally fitted out by bonzi for someone else and cost arround £6,000 ish including the paintjob.The hull alone costs arround £500 i believe but Wayne bought it for considerably less after it had only been run maybe 2-3 times,a bargain you could say but still out of my price range.He gps'd it at 58 mph but he reckons it will do over 65 in the right conditions.Its def a work of art and its 67" long.
Mart
heres cpl more videos of it
http://uk.youtube.com/watch?v=tKbG-or4vzU (http://uk.youtube.com/watch?v=tKbG-or4vzU)
http://uk.youtube.com/watch?v=m8Ac6-saaxg (http://uk.youtube.com/watch?v=m8Ac6-saaxg)
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A far better boat?
http://bonzisports.com/classic_info.html (http://bonzisports.com/classic_info.html)
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84 inches...
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Well its bigger not better :} i forgot to add earlier the cto3 has twin bonzi 4s for power.
Mart
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Then that is a very good boat... Shiney hardware in a variety of colours - What could possibly be wrong with it?
Oh and the 84" classic comes with 4 4's
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Naaa, this one! - http://bonzisports.com/classic_showroom.html (http://bonzisports.com/classic_showroom.html)
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Yes that is it martin, the Bonzi 84 classic is an Apache...
http://bonzisports.com/catalogue/index.php?cPath=22_50 (http://bonzisports.com/catalogue/index.php?cPath=22_50)
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Actually i prefer this one,nope its not available it was built to order by the sponsors of the real one,a friend from the states just bought it this spring from the guy who did own it,it cost over $15 k :o,heres a cpl of pics at its unveiling also loads more on his pic site ,nice pair of twins ehh :D
Mart
ps still waiting for some video from him of her running
http://imageevent.com/justaddwata (http://imageevent.com/justaddwata)
GOTTA LOVE THOSE COCONUTS LOL
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You too can own your own model of the "KING OF SHAVES" for £749.99!!!!
(http://i10.ebayimg.com/04/i/001/14/87/dce2_1.JPG)
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=140322438017#ebayphotohosting
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Very Nice. But what they don't tell you it is fitted with a VERY Noise Ex pipe. You should not run it at your local park as you will get chucked out, and it is NOT OMRA legal. :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :((
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Thats the boat that started this whole discussion...
A challenge for you all, if any of you out there can find me a Japenese / Chinese / whatever-ese RTR boat that DOES NOT need a lot of work doing to it, or a few hundred pounds spending on it, or has an out of the box range of more than a few inches, then I shall be so amazed I may just explode....
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Thats the boat that started this whole discussion...
A challenge for you all, if any of you out there can find me a Japenese / Chinese / whatever-ese RTR boat that DOES NOT need a lot of work doing to it, or a few hundred pounds spending on it, or has an out of the box range of more than a few inches, then I shall be so amazed I may just explode....
Some of the American-ese RTR boats are getting a very good rep. The Aquacraft boats especially are making a name for themselves.
http://www.aquacraftmodels.com/
Supervee 27, Miss Vegas, Nitro Hammer, VS1 spring to mind - although the VS1 is only "almost ready to run"
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The SV-27 is reviewed by Trevor as being 'ok but not fast', the Miss Vegas and Nitro Hammer feature non waterproof radio boxes and useless engines....
I am trying believe you me to find a decent RTR, thought I'd found one in the Thunder Tiger Bandit, but the engine mounts fall apart and the engine itself is held on with screws not bolts, and the radio box is rubbish, with far too long pushrods that bend...
Not sure about the VS1 though, not seen one yet, only down point I can find is that it's electric ;)
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The SV27 and VS1 are definitely geared more towards the "serious" part of the market. The involvement of Mike Zabrowski (Grim Racer) - certainly helps give some of their products more credibility. They offer various upgrades for the SV27, but it is supposed to be pretty adequate out of the box. As far as speed goes, the Nitro version is allegedly good for almost 40MPH with an upgraded prop, and nothing else. Pretty impressive for an RTR with a .18 Nitro engine.
The VS1 is designed for a .21 Nitro engine. Don't think the engine comes with it though, so I suppose you can take it out of the RTR category.
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Sorry getting the VS1 and UL1 confused...
Anyway what you need is one of these....
(http://i288.photobucket.com/albums/ll184/andyn_01/Capture.jpg)
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Very Nice. But what they don't tell you it is fitted with a VERY Noise Ex pipe. You should not run it at your local park as you will get chucked out, and it is NOT OMRA legal. :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :((
Just install your own internmal stinger its easy and it works exellent.all you need is some tubing the same diam as the internal part of your outlet on the pipeor stinger as its sometimes called then slide it in as far as the widest part of the pipe or centre of band etc,allways good to drill a small hole in your new internal stinger tube just where the pipe converges to the stinger so as to drain out the oil ,slide it in and either fasten with a pop rivett or silver solder in place.By all accounts it will quieten any noisy pipe to legal limits and it doesnt hurt the performance in fact some say it can improve it and for an extra quiet pipe you can also add an add on muffler ok2.
Mart
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Interesting! I've seen a 3 engined Hydro but not a 4 engined.... anything RC!!!
Know anything more about it Andy?
(http://i288.photobucket.com/albums/ll184/andyn_01/Capture.jpg)
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Very Nice. But what they don't tell you it is fitted with a VERY Noise Ex pipe. You should not run it at your local park as you will get chucked out, and it is NOT OMRA legal. :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :((
Just install your own internmal stinger its easy and it works exellent.all you need is some tubing the same diam as the internal part of your outlet on the pipeor stinger as its sometimes called then slide it in as far as the widest part of the pipe or centre of band etc,allways good to drill a small hole in your new internal stinger tube just where the pipe converges to the stinger so as to drain out the oil ,slide it in and either fasten with a pop rivett or silver solder in place.By all accounts it will quieten any noisy pipe to legal limits and it doesnt hurt the performance in fact some say it can improve it and for an extra quiet pipe you can also add an add on muffler ok2.
Mart
Mart, No arguments with the concept of an internal stinger. But, assuming that the pipe was correctly dimensioned in the first place, the internal diameter, of the new, internal stinger, needs to be the same as the internal diameter , of the original stinger. If the wall thickness of the internal stinger is less than the original, you may be able to drill out the i/d of the original stinger to the o/d of the internal stinger - then slide it in. If not, you need to replace the original stinger with the internal stinger. If you just make an internal stinger to slide inside the unmodified original stinger, you are significantly reducing the diameter of the stinger, and altering the characteristics of the pipe. If the pipe was previously well designed, this will cause power loss, excessive back pressure, excessive heat, and quite possibly engine damage due to detonation.
Properly implemented, an internal stinger will reduce noise significantly, and probably without power loss or other ill effects. I don't think it will reduce the noise from an open pipe down to OMRA / MPBA levels though. It may just about work for the (10dB higher), permitted levels in the US, but radiated noise, and the noise received by a measuring device depends on many other factors as well.
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Sorry getting the VS1 and UL1 confused...
Anyway what you need is one of these....
(http://i288.photobucket.com/albums/ll184/andyn_01/Capture.jpg)
I'm still waiting for the earth shattering kaboom - from the "amazing exploding Andy"....
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Interesting! I've seen a 3 engined Hydro but not a 4 engined.... anything RC!!!
Know anything more about it Andy?
(http://i288.photobucket.com/albums/ll184/andyn_01/Capture.jpg)
Infact I do yes, it's what I'm running at Llanberis and Wiki park next year ;)
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Very Nice. But what they don't tell you it is fitted with a VERY Noise Ex pipe. You should not run it at your local park as you will get chucked out, and it is NOT OMRA legal. :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :((
Just install your own internmal stinger its easy and it works exellent.all you need is some tubing the same diam as the internal part of your outlet on the pipeor stinger as its sometimes called then slide it in as far as the widest part of the pipe or centre of band etc,allways good to drill a small hole in your new internal stinger tube just where the pipe converges to the stinger so as to drain out the oil ,slide it in and either fasten with a pop rivett or silver solder in place.By all accounts it will quieten any noisy pipe to legal limits and it doesnt hurt the performance in fact some say it can improve it and for an extra quiet pipe you can also add an add on muffler ok2.
Mart
Mart, No arguments with the concept of an internal stinger. But, assuming that the pipe was correctly dimensioned in the first place, the internal diameter, of the new, internal stinger, needs to be the same as the internal diameter , of the original stinger. If the wall thickness of the internal stinger is less than the original, you may be able to drill out the i/d of the original stinger to the o/d of the internal stinger - then slide it in. If not, you need to replace the original stinger with the internal stinger. If you just make an internal stinger to slide inside the unmodified original stinger, you are significantly reducing the diameter of the stinger, and altering the characteristics of the pipe. If the pipe was previously well designed, this will cause power loss, excessive back pressure, excessive heat, and quite possibly engine damage due to detonation.
Properly implemented, an internal stinger will reduce noise significantly, and probably without power loss or other ill effects. I don't think it will reduce the noise from an open pipe down to OMRA / MPBA levels though. It may just about work for the (10dB higher), permitted levels in the US, but radiated noise, and the noise received by a measuring device depends on many other factors as well.
Hi mate i can see what your saying but the guys who have done this mod are very well respected and they say they havent had any issues doing this,Scott Schneider been one.In any case most of the noisy pipes tend to be china pipes which in my experience tend to have over large stingers anyway so reducing its diam will probably benefit its performance as seems to be the case by all accounts.Heres a cpl of links of some how to information etc.By the way funny you mention back pressure as my mate tried his rcmk with one of the better know pipes on the market in the hydro i built him and said it had so much back pressure the boat did all of 5 mph then blew the pipe clean off the header,after several attempts he gave up on it.It was a new cooper quiet pipe,he imediateley changed to a china pipe and it ran like a champ if a little noisy see vid.
Mart
china pipe on comet hydro,first test run.
http://www.youtube.com/watch?v=lLJP0PrWkxs (http://www.youtube.com/watch?v=lLJP0PrWkxs)
http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger (http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger)
http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger (http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger)
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Very Nice. But what they don't tell you it is fitted with a VERY Noise Ex pipe. You should not run it at your local park as you will get chucked out, and it is NOT OMRA legal. :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :(( :((
Just install your own internmal stinger its easy and it works exellent.all you need is some tubing the same diam as the internal part of your outlet on the pipeor stinger as its sometimes called then slide it in as far as the widest part of the pipe or centre of band etc,allways good to drill a small hole in your new internal stinger tube just where the pipe converges to the stinger so as to drain out the oil ,slide it in and either fasten with a pop rivett or silver solder in place.By all accounts it will quieten any noisy pipe to legal limits and it doesnt hurt the performance in fact some say it can improve it and for an extra quiet pipe you can also add an add on muffler ok2.
Mart
Mart, No arguments with the concept of an internal stinger. But, assuming that the pipe was correctly dimensioned in the first place, the internal diameter, of the new, internal stinger, needs to be the same as the internal diameter , of the original stinger. If the wall thickness of the internal stinger is less than the original, you may be able to drill out the i/d of the original stinger to the o/d of the internal stinger - then slide it in. If not, you need to replace the original stinger with the internal stinger. If you just make an internal stinger to slide inside the unmodified original stinger, you are significantly reducing the diameter of the stinger, and altering the characteristics of the pipe. If the pipe was previously well designed, this will cause power loss, excessive back pressure, excessive heat, and quite possibly engine damage due to detonation.
Properly implemented, an internal stinger will reduce noise significantly, and probably without power loss or other ill effects. I don't think it will reduce the noise from an open pipe down to OMRA / MPBA levels though. It may just about work for the (10dB higher), permitted levels in the US, but radiated noise, and the noise received by a measuring device depends on many other factors as well.
Hi mate i can see what your saying but the guys who have done this mod are very well respected and they say they havent had any issues doing this,Scott Schneider been one.In any case most of the noisy pipes tend to be china pipes which in my experience tend to have over large stingers anyway so reducing its diam will probably benefit its performance as seems to be the case by all accounts.Heres a cpl of links of some how to information etc.By the way funny you mention back pressure as my mate tried his rcmk with one of the better know pipes on the market in the hydro i built him and said it had so much back pressure the boat did all of 5 mph then blew the pipe clean off the header,after several attempts he gave up on it.It was a new cooper quiet pipe,he imediateley changed to a china pipe and it ran like a champ if a little noisy see vid.
Mart
china pipe on comet hydro,first test run.
http://www.youtube.com/watch?v=lLJP0PrWkxs (http://www.youtube.com/watch?v=lLJP0PrWkxs)
http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger (http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger)
http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger (http://www.jrcbd.com/showthread.php?t=3569&highlight=internal+stinger)
Hi Mart, Yes, too big a stinger will hurt performance too. As a general rule, too large will hurt top end, but is "safe". Too small will hurt torque, and is less safe. I you start off "too big" on the stinger, and get gradually smaller, power will increase to a point. One danger is that, beyond that point, the power fall off is initially quite small and therefore hard to detect, before detonation starts - potentially destroying the piston. Some of the effects of reducing stinger diameter emulate a shorter pipe. These factors can be compensated by lengthening the pipe, but there are others which can't - like the rate at which the stinger will allow the exhaust gases to escape. As stinger size is one of the easier things to change (like pipe length), it is something that can be tweaked - by those who know what they are doing. Andy Brown, for example, offers different sized stinger inserts for some of his pipes. Which one works best will depend on a fairly wide range of factors (engine, boat, fuel, environmental etc).
If you follow what someone has successfully done before - with the same pipe, engine etc, there should be a good chance of success, and I certainly wouldn't dispute people like Scott Schneider's ability, and to some extent that is the key (ie they know how to interpret the results of changes they make). I just didn't want anyone to think you could do this blindly with any pipe, and expect it to work well. If you keep the stinger diameter the same, you should be able to run quiter with less unknowns, and with a higher probability of no adverse effects. Ideally, this should really be done without changing the length of the stinger either. Lengthening the stinger also increases its flow resistance - though to a lesser extent than reducing the diameter. By sliding a pipe into the existing, unmodified stinger, you are making it longer and smaller.
The earliest reference I have seen to the internal stinger, was from the "Two Stroke Tuner's Handbook" by Gordon Jennings - written circa 1973. Jennings wrote that he stumbled across the idea - by sliding the whole length of the stinger into the baffle / converging cone - trying to make a shorter pipe. He later discovered that it had been documented a few years previously.
Sorry it's a bit of a long post again. I'm trying to avoid going into tuned pipe theory in any great depth.
Ian
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Ian not a problem about the long post its all good info,i see where your coming from .My idea about adding the internal stinger was to do this to the china pipe knowing these things are loud and tend to have the extra large diam at the stinger(i should have made that clearer ),that said ive seen lots of guys doing it to many different pipes over the pond and they dont seem to be encountering too many problems .I intend trying it on my old 2" band ali pipe this summer so ill let you know how i get on.
Mart
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Ian not a problem about the long post its all good info,i see where your coming from .My idea about adding the internal stinger was to do this to the china pipe knowing these things are loud and tend to have the extra large diam at the stinger(i should have made that clearer ),that said ive seen lots of guys doing it to many different pipes over the pond and they dont seem to be encountering too many problems .I intend trying it on my old 2" band ali pipe this summer so ill let you know how i get on.
Mart
Good luck. I'm sure it will be fine - and quieten things down a lot. Since we were talking about RTR boats, and in the context of your comments, I probably went off on a bit of a tangent. I don't think it is likely to cause a problem with a "mild" engine. A lot more likely to be a problem with a highly tuned one.
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Getting back to the topic of rtr by far the best according to popularity in the states seems to be whhobbies line of packages,these are sports boats although they do now have a racer that hits 60 mph out of the box pitty the shipping costs would kill the deal for those in the UK.I myself would like to offer some rtr sports boats in the future using quallity hardware and zenoah ,rcmk motors and for those on a budget a good quallity air cooled motor which i will port a little, nothing drastic though for a gain in performance.The motor has proved reliable for me in the past with over a years running,should match a stock zenoah with tuned pipe.Im building one right now for someone and hope to have it tested very soon so i hope to have any bugs sorted out before i send it out to its new owner.If its a racer you want we all know about Daves boats etc but for RTR sports boats there arent many good quallity RTR ones available especially in the UK.Most use poor hardware or poor motors or both and then charge 500 quid and more which i find annoying because they just disapoint the newcomers into the sport.Not sure the king of shaves is worth the £700 price tag either although the hull does look very scale like and i personally like it but im not sure about the package as a whole for the money.Seems theres a big market for a good quallity RTR package if you use quallity running gear .
Mart
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Why not just "inject" the exhaust cooling water into the tuned pipe and expell it via the exhaust gases?
It will quieten a noisy gas (petrol) pipe but there may be a small power loss.
Over to you, Mart & Ian
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Quite a few guys do that but usually they have the water entering the add on muffler,seems to work ok but i personally havent tried it.Wet pipes as you suggest i believe dont produce as much power but im sure Ian will correct me if im wrong ok2 but for a non race boat might be an idea,personally i hate the idea of having water entering the pipe id be worried each time i picked the boat up water would run back i into the motor if i forgot to tip it the right way.
Mart
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I THINK (correct me if I'm wrong) that MHZ do a wet pipe.
A friend of mine has a Sea Queen that has a wet pipe, works well apparently but he hasn't run it in a while.
I don't think it'll do much good to a race boat.
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Hi All
Ive just got hold of a king of shaves boat on ebay, its only been run for 5 mins and the owner said it was to quick for them LOL 490.00 good deal a :-)
Very smart boat nice paintwork but the first thing to go was the Sikk motor i have replaced it with a Zen that i brought fron prestwich some while ago
Also the radio was crap so that gone and ive fitted my 40 meg futaba
Its nice to have a cat that looks like the real thing as i also own 2 racing cat ill keep those for racing !
I have read that some people are slagging off the rudder hardware saying the top end is plastic !! its not its alloy and powder coated black
Any way well pleased and cant wait for a good day to take it down to hove to run it
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Hi
Just one thing. 40MHz & a sparky engine!!! Do your self a favour get a 2.4GHz set. YOU WILL GET interference probs
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You wont have any problems with FM radios just be sure to run a resistor plug and you will be fine.Also ditch the champion plug that comes with the zenoah its junk and will break and the bits go inside the jug and you will ruin a good motor,swap it for an NGK CMR7H resistor plug.The 2.4 ghz is great so long as its futaba fasst,forget spektrum unless you use the new marine rx version .Fm is cheap though and works fine ive never had any isues with it on petrol boats but 27 meg AM is a big no no though.
Mart
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We look forward to your photos Ducati Dave :-))