03 WR450 wont start

I just monted my 480 big bore on my 03 wr 450. Problem is that it wont start. When I try to start it on gear It tries to start, but it is a lot of knocking in something in the engine.

I saw there was 3 marks on the flywheel for the camshafts. I have the hotcams both on intake and exhast. I used the 3rd timing mark. Is that wrong. In the book it says only one mark, But I have 3of them with about 5 mm between. Can it be that it is a tooth wrong on both intake and exhaust?

What else can be the issue?

thanks guys

Yes I would contact hot cams and ask them about the markings. However that can definatley cause it not to start.

Also if you had them way off you can really do some damage to the motor. Refrencing the valves.

....but it is a lot of knocking in something in the engine.

:thumbsup: That's not good.....I would not try to turn the engine over until you look at the cam timing again!

i would check the cams cause it can cause alot of damage to the big bore kit you just got. you wouldnt want to do that

the timing marks on Hotcams for that machine should go as follows...the two marks that are 180* from each other should be flush with the gasket surface, the third mark should be at the 12 o'clock position.......that is if the sprockets have not been moved on the cam.

Okay. Now I figured out my compression problem. I had used too thick shims.

got that sorted out. so now the starter wont crank the engine due to the short decompression pin on the hotcams.

I called my yamaha dealer regarding the timing marks. on the flywheel he said there shoud be 2 marks. I have three marks as following: |-| | those are the marking. between the one to the left and right it is one tooth on the cams. Which one should I use?

The |-| marking is for ignition timing, ie the spark will fire somewhere between the two marks (it varies due to engine RPM and throttle opening). The | is top dead centre, ie when the piston is right at the top so use this one.

The |-| marking is for ignition timing, ie the spark will fire somewhere between the two marks (it varies due to engine RPM and throttle opening). The | is top dead centre, ie when the piston is right at the top so use this one.

Okay thanks alot! This is the one I've used. pure luck I guess. Hope the bike starts today:ride:

Hi, did you mange to get it sorted?

I am having similar problems with my Hotcams..................

YES! The bike started nicely! No chance to use the starter motor, but the kick is just fine. Need to get it to TDC before kicking it hard down.

The next issue is that it went hot very fast and very hot.

I have no Idea wheater it is rich or lean.

I use JD Jetting red needle at 5.th clip, 172 Main jet 48Pilot jet. 1.5 - 2 turns on the screw. I didn't run the bike for long. just some first and second gear. Need to get an AF logger or similar before I start to use it rough

YES! The bike started nicely! No chance to use the starter motor, but the kick is just fine. Need to get it to TDC before kicking it hard down.

The next issue is that it went hot very fast and very hot.

I have no Idea wheater it is rich or lean.

I use JD Jetting red needle at 5.th clip, 172 Main jet 48Pilot jet. 1.5 - 2 turns on the screw. I didn't run the bike for long. just some first and second gear. Need to get an AF logger or similar before I start to use it rough

That sure looks rich to me even for negative altitude but I don't know anything about hot cams.......sorry. My bike gets hot if I run in 1st or 2nd for 5-10 minutes.

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