EthansDad
01-26-2012, 07:40 AM
While prep'ing our bike for next year, I think back to all the DNFs we had in the past due to something mechanical, or the type of break downs I see most often on these minis at the track. Thought I'd put together a top 10 list of the "most common break-down DNF issues". I'm sure others will have some to add or change up.
disclaimer - this is not a knock on any brand of mini - any bike taken to the level we ride is going to have something break....
#1 - worn out spring - bogged out
#2 - broke axle
#3 - thrown chain
#4 - blown top end
#5 - broke frame
#6 - fouled plug / too rich
#7 - Other CVT failure - belt, melted rollers, etc
#8 - Kill Switch Failure
#9 - air leak / too lean - see #4...
#10 - exhaust pipe bolts backed out
how to (try) to avoid...
1 -keep it fresh! $20 is nothing compared to a DNF
2 - keep the axle nuts tight, and watch for bend in axle. keep a spare, change when first see bend. replace OEM axle with aftermaket if your class allows.
3 - proper tensioner position, quality chain, and keep your frame straight!
4 -keep it fresh! 3-4 races on a top end is a lot. carry a spare top end complete and freshen the top end every 3-4 races
5 - pre-season work is what saves you - go the extra mile on frame reinforcement - a few extra Lbs is nothing on these minis, and the frame needs all the love you can give it
6 - keep an eye on weather conditions - rain, storm fronts, etc can make your perfect AM jetting run like crap in the PM.
7 - keep it fresh, and know the limits (in terms of laps, or how hard you can drive it) - pre-season ride until failure so you know what holds up and what doesn't.
8 - they all die. Keep a spare! - look for the motor running on a bit when you take the tether off - that is first sign - replace!
9 - listen to your bike! air leaks happen, and cause a fast idle, or when you blip the throttle, the rpms are very slow to return to idle. find/fix air leak or #4 is about to happen to you.
10 - what it says, its very common. loctite and still check them every moto. same for the silencer core - those pop out a lot too.
disclaimer - this is not a knock on any brand of mini - any bike taken to the level we ride is going to have something break....
#1 - worn out spring - bogged out
#2 - broke axle
#3 - thrown chain
#4 - blown top end
#5 - broke frame
#6 - fouled plug / too rich
#7 - Other CVT failure - belt, melted rollers, etc
#8 - Kill Switch Failure
#9 - air leak / too lean - see #4...
#10 - exhaust pipe bolts backed out
how to (try) to avoid...
1 -keep it fresh! $20 is nothing compared to a DNF
2 - keep the axle nuts tight, and watch for bend in axle. keep a spare, change when first see bend. replace OEM axle with aftermaket if your class allows.
3 - proper tensioner position, quality chain, and keep your frame straight!
4 -keep it fresh! 3-4 races on a top end is a lot. carry a spare top end complete and freshen the top end every 3-4 races
5 - pre-season work is what saves you - go the extra mile on frame reinforcement - a few extra Lbs is nothing on these minis, and the frame needs all the love you can give it
6 - keep an eye on weather conditions - rain, storm fronts, etc can make your perfect AM jetting run like crap in the PM.
7 - keep it fresh, and know the limits (in terms of laps, or how hard you can drive it) - pre-season ride until failure so you know what holds up and what doesn't.
8 - they all die. Keep a spare! - look for the motor running on a bit when you take the tether off - that is first sign - replace!
9 - listen to your bike! air leaks happen, and cause a fast idle, or when you blip the throttle, the rpms are very slow to return to idle. find/fix air leak or #4 is about to happen to you.
10 - what it says, its very common. loctite and still check them every moto. same for the silencer core - those pop out a lot too.