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07 rebuild hard to kick!!!!

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I rebuilt my 07 crf 450r.New kibblewhite HD valve springs,kibblewhite valves,seals ,t chain,wiseco piston and new cyclinder and everything else to do the top end.But i noticed ever since the rebuild when i feel the kicker and set it to tdc to kick it over it kinda feels like its getting hung up.Kinda like a flat spot where it feels like it almost dont wanna budge but when i put all i got into it it fires right up.Its almost easier if i force the kicker to the next notch inbetween tdc.Any ideas.Runs awesome and motor sounds tight.just never did it b4.Im gonna check my valves and everything.Maybe 10 hours on the rebuild but did it since day 1 when rebuilt.I questioned the decomp pin set up but i figured if that was an isssue and it was binding up it would cause running issues where the decomp pin would not compress in.

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My 06 did this after some work was done to it at a shop. turns out they didnt line up the timing marks correctly,they were off by one tooth. it took me awhile to figure it out,you need to line up all the marks.there is two on the bottom one on each side and the one on the cam gear. this was ecactly how mine acted till i fixed the timing. :moon:

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so bike would run fine off a tooth on the timing.i am gonna be checking everything all over again.lol.

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The bike runs fine even if the timing is of by one tooth! So most likely this is your problem.

If the decomp does´nt work, its almost impossible to kickstart the bike.

A tips is to remove the sparkplug and feel the piston to realy bee TDC, then check the markings, the OEM flywheel has two markings next to eachother so it can be a bit tricky to know witch one to go for... I always remove the inspection plug on the engines right side to, just to se that the marking is spot on there to.

Kalle

Ps: When checking the markings, you MUST look at it from a 90 degree angel from the side, move your head up or down a bit makes it look like the timing is of! On the camsprocket you have two marks, one pointing to front and one to rear, it´s easy to see if they are lined straight or not.

Edited by SweKalle
A fill in....

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So, what you're saying is to find TDC off of the piston (not the crank) and then set the cam marks from there?

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You are 1 tooth off on the cam. The 07 is the first year of the weight style decomp on the cam gear:

Flywheel mark:

JT001.jpg

Cam marks:

07cam1.jpg

I highlight the points in red. The hash should line up with the arrow on the tower with the ignition TDC mark in pic 1.

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so use the flywheel mark.I used the other side.I will use all three and put a long screw driver in the cyclinder.A mechanic i knew said it sounded like it need a crank.didnt sound right.I had my buddy call Mark Baldwin that builds his race motors and he said sounds like timing is off by a tooth.LOL.That would explain why when it stalls its such a bitch to start.

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The right side is to time the counterbalancer. Nothing to do with TDC or ignition. THe only thing that is helpful is to make sure you are not 180* out

The left side is the stator with the TDC marks on it.

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so use the flywheel mark.I used the other side.I will use all three and put a long screw driver in the cyclinder.A mechanic i knew said it sounded like it need a crank.didnt sound right.I had my buddy call Mark Baldwin that builds his race motors and he said sounds like timing is off by a tooth.LOL.That would explain why when it stalls its such a bitch to start.

Duh, that is what numerous replys have been

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When I did the top end on my 05, I lined up all three marks, set the cam chain tensioner, and then had my son rotate the engine slowly several times while I watched the timing marks to make sure they lined up perfectly on every rotation. It started on the 3rd kick and has run perfectly ever since. Timing is so important, always take your time when setting the timing on any engine.

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The right side is to time the counterbalancer. Nothing to do with TDC or ignition. THe only thing that is helpful is to make sure you are not 180* out

The left side is the stator with the TDC marks on it.

:cheers:

It´s true the right side marks is for counterbalancer lineup, But it´s also the markings to use to determine TDC, that´s why you have the triangle marking in the inspectionplugg on the right crankcase.

(If you look at the manual they dont even mention the leftside flywheelmarkings to find TDC)

The flywheelmarkings is actually for ignitiontiming only. For example you do not have any markings on trailtechs flywheels?

And you can´t determine 180* off on neither side of the crankchaft, that you can only readout from the camshaft, making sure cam lobes facing up. :moon:

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Pull your valve cover back off and check to see if the decomp pin is inside the lobe of the decomp shaft. If not you would have the problem you describe. The decomp is different in the 07 and the 08. sounds like you decomp to me.

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Just make sure the decompression pin slides in and out freely when i push the decomp weight to the other side like the manual says right.

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Just wanted to say thanks for the help on this. After a complete top end on my '04 (piston, rings, new head & valves) I put it all together, lining up all the crank marks to set the cam timing and everything seemed fine. Granted, it was a bit harder to kick over than before but I thought it might be just more compression from the new piston & rings. It started right up and ran ok at first. I took it out last weekend and rode it for an hour or two and I could tell something was'nt right. Definately harder to kick over, sometimes really hard to start and a lot of popping on decel. So with your advice I dug back into it and checked actual DTC (off the piston)- both crank marks are way off! So I reset the cam timing off of actual TDC and presto, it now runs like its supposed to. So I just wanted to say thanks for your help - without it I might still be trying to figure it out.

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