OzVMX Forum
Clubroom => Bike Talk => Topic started by: Rosco400 on September 22, 2009, 08:28:57 pm
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Have a complete 73 250 maico which wouldnt mind setting up as a dirt tracker, would like a 250 fourstroke to make competetive but looking for opinions/reason to which motor would be beneficial to compliment the bike. Open to British or Jap but want motor sitting in bike to look aesthetically correct i.e, as if it was meant to be.
Cheers :)
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If its complete whats wrong with the Maico motor,
If you want to go four stroke look at what # 52 was doing to the pre75 over 50's at Barleigh ranch.
250 Honda motorsport engine tweeked ;D
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Hey Rosco,
Brit motors are going to be very thin on the ground in that capacity size...things start to get interesting at around the 400cc level, but even then, many are pre-unit and as such might need more space than you have. You could forget conventional wisdom and try and do something with the Matchless semi-unit/unit 250 found in amongst other things the G2CS. This is a link to the 'model' you're after:
http://www.flickr.com/photos/kernowcopia/3921048132/
Bikeboneyard have a cheap one for sale here:
http://www.bikeboneyard.com/matchless.html
Make no mistake though, this is still a big unit for its size, especially across the cases. Its a bit of a shame it was never developed by the factory. Interestingly they did make a scrambles version (as in the picture maybe), so hotter cams must have been available at one time. Maybe not enough to persuade you not to go Jap, but I would personally like to see what could be done with these motors..
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As if Rosco would even see the bike on flickr
noel
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As if Rosco would even see the bike on flickr
noel
I kinda checked out some kinda motor :D
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Don't do it Rossco. To cut up a complete Maico to undertake a less than satisfactory engine swap is a bit sad. The stock Honda XL Motorsports frame is fine once you grind all the crapola off it . To answer your question though, the Honda 250 with a 305 kit is my favourite. Gearboxes last much longer than in the big strokers.
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what about a C15? I hear they go alright :P ;D
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If its complete whats wrong with the Maico motor,
If you want to go four stroke look at what # 52 was doing to the pre75 over 50's at Barleigh ranch.
250 Honda motorsport engine tweeked ;D
Motors Good, just looking what may be achieved,
#52 was inspirational and it sounded sweet running around, think ive hear louder posty bikes, that 250 motored like ive not seen, it seemed to have so much more than anything else in the class 8)
Hey Rosco,
Brit motors are going to be very thin on the ground in that capacity size...things start to get interesting at around the 400cc level, but even then, many are pre-unit and as such might need more space than you have. You could forget conventional wisdom and try and do something with the Matchless semi-unit/unit 250 found in amongst other things the G2CS. This is a link to the 'model' you're after:
http://www.flickr.com/photos/kernowcopia/3921048132/
Bikeboneyard have a cheap one for sale here:
http://www.bikeboneyard.com/matchless.html
Make no mistake though, this is still a big unit for its size, especially across the cases. Its a bit of a shame it was never developed by the factory. Interestingly they did make a scrambles version (as in the picture maybe), so hotter cams must have been available at one time. Maybe not enough to persuade you not to go Jap, but I would personally like to see what could be done with these motors..
I would think stock motor would be a bit of a slug, dont know much about them
Don't do it Rossco. To cut up a complete Maico to undertake a less than satisfactory engine swap is a bit sad. The stock Honda XL Motorsports frame is fine once you grind all the crapola off it . To answer your question though, the Honda 250 with a 305 kit is my favourite. Gearboxes last much longer than in the big strokers.
That has been my thoughts for a while with it as well, just weighing up the options, would like good set up pre 75 dirt tracker tho and have this spare sitting away doing nothing
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Don't waste a good bike,With the result on at the Ranch on the weekend in the over 50 yrs 250 cc race the modifications Pete #52 has made to his Motosport 250 (to be precise 262 cc legal engine for the class).Pete would have liked the engine stripped down to confirm the fact. This is a cheap ticket using modern bits only top end stuff(you will have to do the rest of the thinking from here on as we are a fairly secretive bunch here in the Godfather capital) & easier to ride then the two strokes. ;D
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Pete would have liked the engine stripped down to confirm the fact. This is a cheap ticket using modern bits only top end stuff(you will have to do the rest of the thinking from here on as we are a fairly secretive bunch here in the Godfather capital) & easier to ride then the two strokes. ;D
C'mon stripping it down was the last thing it needs, running to sweet for that, sounded close to a 250 to worry about that stuff, now bit of expansion on the secretative stuff is what we need to know, ive heard bunnings 750 watt generators revving harder :D
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That 250 of your sounded like a hairy goat Rossco plus good 4T engines are in the same league santa claus and the tooth fairy. I've seen a 250 Maico and they would be a doddle to get some serious torque out of.
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Firko shame you left before lunch break on Sunday as Pete & I went for a wander around the track then for a yarn with you, but you had disappeared.
Regarging the XL 250 gearboxes they are fairly tough as that is what we run in our big bore 350 engines close ratio compared to the stock 350 box . The engine I use is on it's second 250 gear train after 14 yrs & about 6 big ends (until I went to the Carillo option)when assembled carefully they are near bullet proof.
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doddle
??? whats a doddle Lozza
The motorsport is an option and suspect spares would be plentiful.
Maico produce its first 4t engine in what year Firko, just another brainwave
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Yeah mate, sorry to have to leave early but this shit happens a lot lately.
I ran a stock bore 350 with Carillo rod, Venolia 12:1 piston, Megacycle roller cam, welded up rockers, some nice portwork and 36mm Amal concentric in my Champion frame back in the 90s and had a hard time keeping 3rd gear in it. I also ran a 420 engine, stock other than a mild cam and the Henry Abe big bore kit and had the same 3rd gear hassles. I was using a Mk8 Bultaco rear hub with no cush drive so I decided to change over to a Yamaha DT250 wheel with cush drive and the gear problem disappeared. The third engine I had was the 305 Yoshimura stage 3 engine and it hooted. I've been offered my old 350 engine back from the current owner and I'm tempted. That thing dug trenches.
I may be taking a drive down to visit friends in Yenda later in the year so I'll look you guys up for a beer or two and talk about some upcoming "things".
Maico produce its first 4t engine in what year Firko, just another brainwave
Maico never released a production 4 stroker Ross.
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Maico produce its first 4t engine in what year Firko, just another brainwave
Maico never released a production 4 stroker Ross.
Ok, thinking of the grafts I saw in another thread, too technical for me :-[
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That 250 of your sounded like a hairy goat Rossco plus good 4T engines are in the same league santa claus and the tooth fairy. I've seen a 250 Maico and they would be a doddle to get some serious torque out of.
Sure, Maico 250's can be made to work. Gary Treadwell did mine and did a very fast one for Cary L'estrange in Condoblin a few years ago but they become a bit unreliable (unless you use a Yamaha rod and big end kit). The biggest thing to overcome with a ported 250 Maico is the 4 speed box. If ever an engine needed a 5 speed it's the Maico 250.
good 4T engines are in the same league santa claus
Did you get run over a 4 stroke when you were a kiddie Lozza? Have you ever considered that some of us might like 4 strokes?
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I never even crossed my mind :o. I've never owned (and likely never will) own a 4T motorcycle. I see they sell them so somebody must like them, but I see they sell Andre Reiu CD's to.Each to their own I suppose.
Making your 250 Maico go Rossco that's a doddle.The engine has to work with the gearbox for sure. It might only need 1 ratio changed ;)
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It might only need 1 ratio changed
Which would be? It's a bit of a problem when all Maico 4 speeds are the same ratios. As for gearing, you can always get a compromise but you'll never get the ideal. You don't see too many 250 Maicos blitzing the field for that reason. It's not a problem for the 400/440 because of the great torque available.
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Have tried a few gearing combinations Lozza and try as you might, the 4T get the power to the ground much better than the 2T.
In the Pre 78s 263 and over, I had the 77 AW honking but could only manage a 5th in the final as the 4T made the 2T look stupid off the start line and they were some of my better starts on the day. Unfortunately, you cant win races from the back of the pack on the start grid.
Ray Stevens power to the ground on the 500 was amazing to watch when you sitting behind him (not thru choice I might add :-[) but it was what it was. I spoke to one of the other guys in the same class who has a long racing history and is no slouch and he had formed the same opinion and couldnt get his 2T to the front either, I cant remember the results overall but I would believe 4T finished 1,2 & 3 in the pre 78s.
Now saying this, i believe the 2T are still the go on th MX side of things and In not about to change the whole Maico stable over this issue, just would like a DT bike that is able to get the power to the ground smoothly and consistantly, sure its all got to do with the firing of the engne but I'm just not that technically advanced,I just like riding and observing ;D
It might only need 1 ratio changed
Which would be? It's a bit of a problem when all Maico 4 speeds are the same ratios. As for gearing, you can always get a compromise but you'll never get the ideal. You don't see too many 250 Maicos blitzing the field for that reason. It's not a problem for the 400/440 because of the great torque available.
I do have to say the 2T did finish 3rd in the pre 70 open against the big bores and was quick thru the dog leg because of the gearaing and weight issues, (no not mine) I reckon my old square barrell has more tow than the 400. Saying that , Keith Stacker had done a little head work with it ;)
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Could well be Rossco, the 4T will fire once every 720deg of crank rotation and the 2T once every 360deg of crank rotation. The idea is still used today on MotoGP engines. Theory on why is due to the 'gap' in the torque pulses allowing the tyre time to recover and find grip before the next torque pulse comes.Well that's what Warren Willing said and I'll run with that.
With a Maico 250 putting 27 HP or so at the wheel it's probably 5-10HP down on a good DT engine. Your yellow bike sounded a lot like it was bouncing off a rev limiter the times I heard it.You were up against some well sorted packages and that's different to throwing on a trials tyre and riding.
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have a Maicosport and did not cut the frame but used centre port possn for mikuni,305 big bore etc one of my favourite bikes.Saw john Peters in 1991 at Dargyl
went home and made one and raced ever since as reliable as sin.Will try to pm you photo later
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XT500 plus good cam plus good piston.
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only they probably won't let you ride in pre 75.
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Dirt track seems to me a bit like road racing , in the run to the first corner is very important and the drive off corners and some top end HP to keep the drive going. I will stand corrected but to me difference is I suppose being able to 'read' the dirt surface and pick where you can get the best drive from(dodging some bumps as well). I would be confident a well set up and tuned 250 2T should be able to mix it with the 4T's.
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Hyjack,
Lozza any idea's on making an RD200/DT175 work ;D
Cheers
Noel
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Sure Noel, the RD 200 no worries the DT I would just keep riding that to work ;D
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the RD is in the DT frame ;D
Noel
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ooooh,i know where your'e going with that combo Noel ;D,twingle perchance ;) 8), :P
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RD 200? ??? What did the Northern Beaches throw out turn up something interesting? A King Kenny style flat tracker is that what you had in mind? 90 deg firing/twingle would work a treat ;)
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fork that get an rd400 and water cool that baby, anybody got a good roller I can slip that into? ;)
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(http://i255.photobucket.com/albums/hh160/rosco400_photos/DSCF4592.jpg)
This photo courtesy of a forum member, this is what I thought looks the part and would be competetive ;)
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The above beauty is Klub Kevlars NZ based social director, Mike Jolleys 'Maicosport' that he's raced on an off for a couple of decades in NZ and in it's one Aussie appearance at the '95 Barrabool Nats.
It's a cool bike but he built it out of leftovers, chopping a perfectly good Maico up to achieve the same would be a crying shame in my humble opinion Ross. Complete old Maicos will always be a better long term investment than a hot rod, no matter how competitive or well put together it may be. If you're still keen on a hot rod Honda it may be a better idea to sell the Maico to finance the components to build a good 4 stroke weapon.
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Should have probably said the 73 is a complete basketcase that has been little butched
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It may be a better idea to sell the Maico
To me!
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No, i'm good ;)
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It was worth a shot Rossco! If you do decide to go the Honda 4 stroke route, would you sell the engine?
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Probably not at this time, dont know as it will be sitting a fair bit longer yet but will let you know if I go that way, I havent got a pre 75 250 running at the but the way Pre 70s are heading, might have to get it going sooner rather than later
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Rosco
What about this one
http://cgi.ebay.com.au/V8-Dirtbike-Inclosed-Trailer_W0QQitemZ220493141292QQcmdZViewItemQQptZAU_Motorcycles?hash=item33566a552c&_trksid=p3286.c0.m14 (http://cgi.ebay.com.au/V8-Dirtbike-Inclosed-Trailer_W0QQitemZ220493141292QQcmdZViewItemQQptZAU_Motorcycles?hash=item33566a552c&_trksid=p3286.c0.m14)
Ed
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No good Ed, it would suck me gut down the inlet ::)