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Fly wheel weight on 125cc


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I know Charlie at the Trials Training Center recommends the flywheel weight for the GG 125.  I rode my '17 GG 125 for 6 months, as a 62 year old 180 lbs novice and never really felt a lack of bottom end.  That said, I have ridden 125/150 enduro bikes for years , so a 125 trials feel like a tractor in comparison......

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Does the gas gas racing 125 you refer to have a Keihin Carb as opposed to a Dellorto.

The reason is ask this is I fitted a Raga Reed valve and a Keihin Carb to my sons bike last week and it is fair to say it substantially increased mid and top end power to the extent the bike was transformed and did not feel like a 125.

The downside however is I think we have lost some bottom end power compared to the previous set up with a Dellorto carb going from a 26mm to 28mm carb.

Very interested accordingly on feedback on potentially fitting a fly wheel weight if that will result in materially increasing torque at bottom end.

At end of day not complaining, as the bikes are pretty good in original format, and it is always a debate if perceived performance gains actually result in less dabs !








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I ride a Sherco 125 every week in a trial - perhaps now around 80 trials on this bike.  However, in the past I have always ridden 250s.  

The thing about a 125 2 stroke trials bike, compared to a 250, is that it completely lacks torque at the bottom end.  Consequently, when ridden by an adult, it is necessary to rev the motor and slip the clutch to obtain power and torque.  It is there, but not at or near the bottom of the rev range.  

The latest GasGas 125 is a bit better than the others IMHO, but still nowhere near a 250.  I don't think that the limited power of a 125 needs a heavier flywheel to smooth the power.  However, it might contribute something else to the power characteristics - perhaps slow down the time that it takes to rev up and therefore slow down.

Why not fit one and report back.  

Edited by stpauls
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Fitted one  to Beta 200, made it very sleepy to respond al low revs which meant I had to slip the clutch to climb rocks, worse than standard. But if you don't use above 1/4 throttle on eady courses it was fine. All my 250's have had one and suit me, the 200 wss the only one I've removed. Youre only adding/changing  inertia, not power. 

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