CRF's Only Forums

So i have been racing yfz/yfzr quads in mx for bout 6 yrs. i do my own motor work. Just picked up a 05 crf since its hard to find tracks to ride quads anymore.

Crf. Stock motor as far as i know. Pro circuit pipe. Bike was raced by a last name humphrey #15 in oklahoma if anyone knows history on the bike. Colt Humphrey maybe?

Anyways. I got it from another guy. Says it runs good. But a pain to start. I cant get it to run. I started off by checking valves. Intakes were .003 and .004 gap. Exhaust was tight at .003 and .007. I think i need to set them at .006 intake and exhaust .010.

My other question. The timing marks on crank gear, cam, and flywheel are not all lined up. Ive seen on a valve adjust how to, to time cam off the cam gear dot on clutch side. Ive seen other post say to time off 2nd mark on flywheel. Which is correct. I feel like flywheel should be correct. And doubt that they flywheel and crank gear should show different marks.

Should like 2nd hash mark on flywheel line up with the crank gear dot/arrow? Cause it is not.

Also, it makes a loud tick noise when turning over motor slow or fast. Seems like the decompression on the cam. Is that normal. Prev owner said it made a wierd lower end noise, but have yet to get it running. Looking for any and all help. Thx

Can anyone help if u need more info. Lmk

I can help with the loud click, yes, that should be the decompressor- normal

welcome to CRF's Only!

tight intakes mean they are on the way out if they are titanium valves. which means shimming them will only get you a few engine hours as most with diminishing returns with repeated shimming. if this is your situation you need to have a valve job and new valves installed.

here's our how-to on valve adjustments:

http://crfsonly.com/howto/crf250x/crf-v ... stment.php

loud clicking it likely your decomp as mentioned. sometimes the decomp will make more noise than normal. try lubing the decomp system with oil. apply the oil to all the small working parts (including that little nub that activates the arm) apply a coat of assembly lube to the arm and surfaces if the oil doesn't work.

again, welcome.

Ken

Thx. Not what i want to hear. But guess i will end up trying new valves if needed after i get it going.

Main question. 2 timing marks to use to line up cams.

Valves how to says use the crank gear on clutch side. If i do that, the flywheel 2mark does not line up in notch of stator cover. Am i incorrect for thinking these 2 marks should line up same, the set cam flush with head

yes they should match up. the reason people use the stator side is its easier to tell if its lined up. if both side aren't close i would pull the stator and make sure the key is in there or not sheared

as long as the cam gear has not moved on the cam just use the cam gear marks and the primary drive gear TDC mark. check the flywheel that it hasn't slipped on the key or the key is missing. if the cam gear has moved or the keys is missing or damaged it's a sign this engine had catastrophic failure and would be a concern. if the cam gear is weld on the cam then it means an engine builder changed the cam timing.

Cam gear has no welds or engravings like its after arket. Supposively motor is stock.

I already pulled flywheel to check if key sheered. It did not. But i ordered a new key and nut as some threads stuck on crank.

I adjusted valves. I put cam in time with drive gear

Can the drive get get off one tooth spline? I assume it is notched so you cant put it on wrong

if anything is off it will be either the cam gear or the flywheel. if it's an aftermarket flywheel i have seen some badly marked flywheels out there. also, there was one report of a badly market flywheel from honda. that was internet hearsay not first hand knowledge.

ken

crfsonly wrote: if the cam gear is weld on the cam then it means an engine builder changed the cam timing.

not always true... they are also welded with stock timing so the gear will never spin

The cam gear is at least pointing to rear of bike. Not sure if its off a tad or not.

Ive got it lined up back with drive gear. Waiting on flywheel key and nut now.
Flywheel number krna 132000-0060 7fy denso japan l vcj70

Is that stock flywheel?

sorry not familiar with those numbers. just the honda part numbers and aftermarket versions.