Hello everyone.. need some advice.. new to trials and just upgraded from 96 160 gg to 09 250 gg.. went out first ride today and the bike is a monster ? very twitchy and fast.. think it might have quick action throttle on it.. will a slower action throttle give a much slower power delivery? Seems to be popping while on low revs making it a bit twitchy while going slow.. could it need exhaust repacking? Any advice would be great thanks 

Edited February 5, 20179 yr by pete_d

I think they came with an 11t cs sprocket. A ten would help.

Thanks will have a look next weekend.. does seem a totally different bike the 160 was very easy to ride and i felt comfortable on it just lacked a bit of punch on the big hills, this one is very touchy just want to throw you off the back 

Hi Pete, my advice would be : 10T front sprocket, slow action throttle (Black Tube), Flywheel weight, definitely re pack tail pipe, middle box packing would make a difference, but is quite difficult to do, Carb settings which I find best assuming you have the std Dellorto Carb fitted are Main Jet 118, Pilot Jet 33,Slide 50,Needle D33, on 3rd notch from top, also mixture screw approx. 3 full turns out, also bear in mind that as its a mixture screw as apposed to an air screw, its out to richen , and in to weaken, any more advice you need just ask, will be happy to help.

Thanks for the info Basecampkid.. I have brought slow action throttle and 10t sprocket will be fitting them this weekend and will have a play with the carb settings before sunday.. will let you know how I get on ?

Is there a how-to on cleaning or re-packing the middle box?

Before accepting a computer based diagnosis i would simply get everything spot on. Give the bike a full service and pay particular attention to the carb spark plug (new) air filter and so on. Do not think one thing will cure any "problems" you may have this is unlikely.

A well set up bike with all controls working as they should is a great starting point.

A slow throttle is no substitute for getting some throttle control by time spent on the bike rather than changing this or that.

Familiarity is the cheapest and most fun. The throttle can be as wild as you like it's clutch control that wins the day. One thing i have played with is the richness of fuel/air. This has calmed my bike down. Try various settings on the same obstacles. A bit of water in the carb will also make acceleration curves erratic...... I learnt that too. Good luck

Changed the throttle to slow action and sprocket to 10t and had a good days riding with lots of practice and it seems a lot more manageable.. exhaust definitely needs repacking but feel a lot more confident on it.. especially with using the clutch more to smooth it out.. even got it over a few decent size logs ? thanks for all the advise