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Compression Stuff

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I've had my 250 Pro now for 4 months and ride it 2 or 3 times a week the motor runs really sweet now with the 33 pilot jet but the question is the compression in kickstarting.It's like I have to stand on the kick to get it to fire up which it does easynow but it just seems to take a lot of effort which can be a pain in stuck up a section situations.Can I expect the motor to loosen up,in relation to kickstarting,I've seen the gasket mod on the GGUK site to lower compression,anybody done this?

I was watching Raga Fajardo and other GG pilots yesterday at the Urbain Trial in Cahors and apart from them being just awesome to watch when it comes to kickstarting it 's just a no effort prod and away you go,Raga's 300 just seems to have amazing soft power I'm sure he could kickstart by hand.I know what I'm after is just a tweek but whats a trials bike without a tweek?

Raga won on 1 damn that kid is good!

H

try putting two gasket kits on the head, you will loose a bit power but easier to start. :angry:

There is a lot in the technique to kick starting a trials bike. if you have kicked a bike over as many times as Raga i bet you would make it look easy. look at it like this, the things he does on a bike, he makes that look so so effortless as if he isn't trying. maybe its the same kind of thing when he kicks it over. technique is everything i reckon.

try putting two gasket kits on the head, you will loose a bit power but easier to start.  :angry:

The Gas Gas kit is a machined spacer and an extra o-ring to fit in the top of the cylinder - not an extra gasket. I have an 03 280 Pro without the spacer and a mate has a spacer fitted. There is a noticeable difference between the two bikes. The spacer makes starting easier and has also softened the power delivery.

  • Author

Thanks for the response W1 interested to know if your mate fitted the spacer himself, is it just head off and no other adjustments with timing and stuff,carb settings etc?Or a workshop job.Curious to try this avenue with slightly softer power.Anyone else tried this mod?

H

The kit is just a head off to fit job. Should not need any carb adjustments.

A friend of mine did it to his 250 03 and when tryed alongside my 250 03 the differance was very noticable. Way to soft for my liking.

He fitted the kit himself without any changes to carb or timing. The beauty of the kit is that you only need to remove the top of the head. Adding bottom gaskets is a bigger strip down. The only "difficult" part of the job was draining and refilling the radiator.

Speak to Gas Gas and they'll tell you exactly what you need to do.

  • Author

Thanks for the advice guys still might give it a go, the spacer's not expensive,just to try the difference,might save the dodgy knee abit on starting,OLS old trialy syndrome!

Any clues on the torque settings for the head bolts?Thanks

H

Find out for sure before you torque.

It's always less than I expect.

Of course, I work on Harleys and Indians, and 50-65 ft/lb is not uncommon.

I bet most trials bikes are 12-15.

i dont thuink this helps but, i would like my 125 gasser to have more compresion at kickstart, feels odd compared to yam.

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