which 250 engine?

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

I am into Karting, atm i have a kart with a Honda cr125 motor on it.

Not too sure of the power but i think its about 30bhp.

I go karting with the lads from work, there is no cc restriction for us as we go testing and race each other. The other lads have Rotax t7 or t9 engines, producing about 35-40 bhp.

The problem is not only is my kart down on power, but i weight a lot more than the others! So my plan now over christmas is to find a 250cc motor for the kart.

It seems that the honda cr250 is a good choice, but there isnt many about and certainly not for handy money.

When i thought about this before, i saw that Aprila do a 250 twin engine that is a V shaped on their RS bikes, cant find one of these for sale anywhere either.

So, the question is, is there another 250 motor out there that does about 45bhp or more that i could be looking for.

thanks!

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

The RS250 engine is just an RGV250 engine with a few minor mods. Being a twin it would probably be more difficult to mount. And if you want to go that much effort then just fit a Rotax 250 disk valve parallel twin.

There is the Rotax 256 which is a 250cc reed valve 2 stroke single. About the power level you want. Sold in enduro spec and also in kart spec (the kart version has far closer gearbox ratios and a few other changes).

However you could probably use pretty much any 2 squeak 250 motocross or enduro engine.

All the best

Keith
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stevo as b4 · World Chat Champion Joined: 17 Jul 2003 Karma :

I'd just keep looking for a Japanese 250cc single cylinder MX engine. Any of the big 4 are as good as each other. You might find that with something like a KTM/Husquvarna engine could be problematic for spares if it's a really old one.

You might be best off looking for a complete but tatty MX bike to use as a donor though, as you can take the engine mounts, exhaust, CDI and anything else you need from it.

stinkwheel · Bovine Proctologist Joined: 12 Jul 2004 Karma :

If there is no cc restriction, does it have to be a 250cc?

Thing is, you can get Yamaha Banshee Quad bike engines which are 350cc 2-stroke paralell twins. They are derived from the famous, early 1980's 350YPVS motor and there is some awe-inspiringly silly tuning stuff out there for them. (720cc being the biggest overbore/overbarrel I recall seeing).
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

chris-red · Have you considered a TDM? Joined: 21 Sep 2005 Karma :

G · The Voice of Reason Joined: 02 Feb 2002 Karma :

MaybeGuy · Super Spammer Joined: 12 Mar 2007 Karma :

Ive got most of an rd350 engine if you do decide to put one in. Would be willing to sell.
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!! Mr. Green

Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

MaybeGuy · Super Spammer Joined: 12 Mar 2007 Karma :

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

MaybeGuy · Super Spammer Joined: 12 Mar 2007 Karma :

missing top end and crank.

its got the gearbox, clutch, generator and a load of other bits and bobs. carbs etc.

id take £100 for the lot
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Blue_SV650S wrote: it was a sh1te wheelie, but it proves that he can get it up in 3rd and can do angles. In summery, mattsprattuk is a gobby little sh1tebag, dopehead tw4t, but sadly for all of us, he probably isn't THAT full of sh1te!! Mr. Green

Kickstart wrote: Hi I tend to agree with Matt. All the best Keith

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

Really interested, do you have the exhaust/s for it? Where abouts are you? [ im near liverpool ] Roughly or if you could how wide is it?

MaybeGuy · Super Spammer Joined: 12 Mar 2007 Karma :

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

I measured my kart again today, and i think it has to be either a vary close V type motor or a single 250... I thought there was going to be more room than that Sad

Shame the 350 sounded just right!

bladerunner · World Chat Champion Joined: 09 Sep 2006 Karma :

The RS is indeed a vj22 RGV motor. it's not an inline V twin if you like ala harleys etc as it's a 2 stroke and needs crank case volume for each cylinder. I do happen to have a few ex race motors kicking about the garage and can measure one up for you if you want to go that route but bear in mind that it will be a fair bit of fiddling to get the exhausts made up etc but the bonus is a genuine 60-65 rear wheel bhp aint a problem to get out of these motors..more if you go mad but get rather fragile at that point. it would be silly quick for a kart thats for sure. I've seen rotax 250 parallel twins used in karts and they were serious fast.....as well as drag raced ones with silly things like gsxr1100 motors and they were still spinning by the end of a1/4 mile drag strip Shocked

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Current bikes...cbr929, KDX200's, Rd125lc mk2, RGV250's

avtovaz · Two Stroke Sniffer Joined: 01 Jun 2008 Karma :

Well, i didnt know the suzuki motor was the same as the aprilia RS!!!

A lad i used to work with had a RG500, that was amazing bike, 4 pipes out the back, sounded awesome!

The only real measurement i need is the width, the cr125 just fitted nice on the cradle i adapted from the rotax motor that was on there before, i took that off as the circuit i goto dosnt like air cooled motors as they recon they are loud! As for the exhaust, as long as i dont mod the sizes of it, just the direction i hope itll be ok. My job is welding and facrication!

The RS motor i think would be the best as its like 2x 125cc motors, not one big piston and crank if you know what i mean.

As i say, the problem is, i am not far off 19 stone, but recon if i had the power i could keep up with the lads who i go with who are well nearly half my weight!

Plus a twin would sound AWESOME Wink

Thanks

)))

bladerunner · World Chat Champion Joined: 09 Sep 2006 Karma :

Ok mate I'll measure it up for you. do you want total width and length..dont forget being a V twin means the engine is longer being one pot faces straight forward and if you want any other dimensions just let me know. and yes being 2x 125 cc engines in a V configuration means it revs higher than a 250 single and also has good traction Very Happy

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Current bikes...cbr929, KDX200's, Rd125lc mk2, RGV250's