Posts
97
Joined
12/11/2011
Location
Buzzards Bay, MA
US
Edited Date/Time
1/11/2015 12:18pm
Hey guys I have a 2014 yz 250 stock except pro circuit pipe and silencer. Bike has less then 2 hours on it. Riding today bike fine for about 10 min then starts breaking up cutting in and out almost like back firing. Get the bike home start it again put it in gear goes in reverse any ideas? Thanks!
The Shop
Luxon 4-Post Bar Mounts
$189.95 - $239.95
Free shipping: VITALMX
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
We had an 03 CR125 that would eat chain sliders in one ride. We called our Honda rep and met him with the bike at he dealership. He took a bunch of frame measurement and said everything looked good chain wise. Long story short Honda took back our bike mid season and gave us a brand new one.
Pit Row
That is why you generally hear a "pop" when you use a puller to remove the flywheel / rotor, as it comes off the taper.
Have seen many keyless race ignitions over the years. It is taper that keeps things in place.
If the flywheel nut was not torqued correctly, the flywheel could have lost it's seat on the taper, sheared the key, and lost timing orientation. Usually ,when that happens, they slip far enough that the bike will quit running.
Once saw my brother dick around with changing ignitions on his Shell 250 Yamaha flat track bike. When installing the flywheel, the key slid out of it's groove as the flywheel was slid on. At that point ,it was hard to see what had happened. Torqued the flywheel down, fired it off, and went out for a heat race. The flywheel had slipped ever so slightly, retarding the timing.
A normally clean running, fast bike, it acted like someone put a #500 main jet in it. It would never clean out and rev. Needless to say, FT race programs run fairly quick, and we did not trouble shoot it quick enough to make the semi.
The old piston port models from way back would occasionally run backwards. Usually advanced timing made them more prone to this.
Check the timing with a dial indicator. Once initial timing is set to spec, the CDI unit is what determines full ignition timing advance.
So did you even check the flywheel location like so many advised?
TM
Mine is running fine, but I did do a full timing check and installed a GYTR flywheel before I ever rode it.
You need to check you piston edges for pitting.
Also, low fuel octane or old fuel mix will cause this on YZ250's.
This issue has been around for years.
Paw Paw
Post a reply to: 2014 yz 250 issues