[lumpdog]

Hi all , im just after some advice and help .
I have just rebuilt the top end of my crfx 250 engine with the full Kibble White valve train . My local Honda dealer re-cut my valve seats and assembled the head , they did get one shim out of spec but i picked up on that when i got it timmed up .
So i timmed her up , i didnt find that the timming marks ever looked that "spot on" i dont know if anyone else has ever found that ??

Trouble is its real damn hard to start , it seems to have so much more compression than before even with my full weight behind it the kickstarter doesnt move on most occasions

I just finisned a 3 hour enduro and i was at good 5 miutes late getting off the line because i couldnt start it , and the few times i stalled it it took a good 10mins off my lap time . I tried all types of hot-start on/off , no throttle/ throttle combinations , even with the choke some times to get it going but none seemed to really have any effect .

I dont know if its an effect of the Kb`s but my bike is now an absolute grunt monster it unreal , but as a result has not top end atall
I had a 125 2t sing past me on a long bumpy uphill section whilst i was pinned in 3rd , so i upped it to forth and nearly got thrown off the back as i flew back past him .

So have i maybe got the timing "out" somewhere and effected the decompression system somewhere down the line , i used to be able to give the starter a minor prod and the CRF would fire right up . Any help will be really appriciated on this one because its really causing my results to slip thanks

[Asmith]

Sounds like you are one tooth off on the timing.

[lumpdog]

I was hoping you would read this Really ? I didnt know if it would still run ok one tooth out , im glad its probably something dead simple then . So do you think i could have damaged the engine atall by giving it so much stick for so long with it a tooth out .

Have you ever thought that the timing marks are not completly accurate ?? Or is that where i am going wrong .

[124]

Lump - You must have something off. I would also suggest checking the timing again. It should be really close, if not dead on. A new topend (factory compression ratio) and stainless valvetrain install should not affect your starting routine at all.

You are setting the timing without tension on the chain right?

[lumpdog]

Erm , yeah i must have been because when i 1st put the cam in it was miles out , and i slipped it out and spun it round to rectify the problem .
Then i couldn`t get the cam in and found that the chain had slipped under the drivegear from the crank and got all bunched up . So a Honda flywheel puller later (with the cap cover ) i unhooked the chain and installed the cam again , i kept the flywheel off for that . I did have to spin the crank through 360 to free the chain and then couldnt remember where i had gone from but a local dealer said that it didnt make a difference what TDC i used as long as i timmed it as ignition stroke not the exhaust stroke
So with the cam chain free and the piston at TDC i reinstalled the cam - loabs facing backwards to the rear fender , and torqued the cam caps down . Then i take the tension off the camchain .

[124]

Did you use the correct mark on the crank gear? There has been confusion regarding this. Apparently, there is mark(s) that are similiar. Something to check.

The advise you got is correct regarding the TDC though. When installing a cam, all you need to do is make sure the piston is at TDC and install the cam on the compression stroke. None of the cam lobes applying pressure on any of the valves.

[lumpdog]

Ok ill have to look around the gear to check for another marker , that would do it easily hey , so whats the other marker for then

Im happy that i get the cam in the correct position regarding firing / exhausts stroke , i give the exhaust follower a wiggle to ensure that there is no tension on it.

One other concern i had was valve clearences . As they are so scritical , how can you safley say that you have the right "feel" when you insert a feeler gauge .
Between two seperate people there could be two completly different measurements , what i mean is one guy may slide .5 into the inlet real loosly and another guy may do it and set it so its really tight ?? But who would be correct

[124]

For any given gap, there usually is only 3 gauges that go in that could be questionable One's tight, one's loose. The one in the middle can be called "the measurement".

The other mark on the main gear: Not sure what it's for, but I know other folks have gotten them confused. The incorrect one is not far off the correct one according to the reports...worth checking.

[lumpdog]

Just thought i`d say thanks for the help , timing adjusted , it was one tooth forward now sorted and its back to good ol minimal effort starting .

[124]