FINALLY someone who actually showed the timing marks on the cam ! Very little info on the web for these bikes.

This video helped with my 79 XL500s. Thanks, man!

Timing looks good.. great video BTW. Just doing mine now and wanted to double check it was correct

My air cut off valve in the carb was really dirty on my 86 xr250 causing it not to run properly. I cleaned carb three times before ever seeing the place where the air cut of valve is located. I read you have it going now, good deal. Hope this helps if it happens again.

Turning the cam lobes downward is the problem. Turn them so the lobes are up and you will see it aligns the timing marks perfectly. Don't worry about the firing order no hitting because the lobes are up. It will not cause any misfiring problems. I learned this after trying to adjust my cam timing many many times.

Cool, I just tore mine apart but got stack on slack adjuster. The timing chain looks like is gona dance and shout like hell. Any help???

Great videos thanks for sharing Shawn..CJ

How do you do to unlock the chain tensioner and put the pin on it?

Well if the crank stopped when the cam shit itself. quickly jammed up the engine i think looking into the keyway shearing would be a good idea. Ive seen keys half sheer before... That would change the timing if that magneto even slightly shifts on the keyway... The plot thickens but i think your on the right track

Holy so precise. Its at TDC you're good to go.

My mechanic said my atv is not timed right but it runs fine and he said it's a huge job

It's funny how you say ''hold that sucker at TDC'' because ''sucker'' is the actual Dutch word for ''piston'' :)

I hope that one tooth difference makes it right. Assuming all components swapped were all good. Hard to say. Hopefully you have good grounding. You have to wait and give it a try once again with what you just did. Hope she works.

1985 xr350r. im at a loss i swear its set perfect timing and it seems like my exhaust valve is hitting the piston???? any ideas?

Hi... I have up the needle on carb... and my cam it's not alingne worst then yours... mine it's running but if you have a solution it will be great... (think that's a theet down, because i can align it). Thanks

That sucks... doing the same thing... I think next step should be inspect the bottom end the pickup coil could it be loose or have a broken wire? Is it adjusted correctly as for gap between the trigger? It may be wise while your in there to pull the magneto check for a broken keyway key if that keyway is loose, sloppy or sheared a bit it could probably cause big timing problems

Can someone tell me the cam timing. I couldn’t read it in the vid

Alguien sabe cuanto eslabones tiene la cadenilla de tiempo ayudeme

Never got that deep into my Kawasaki road bike... 'course, that was a long time ago...

I've got the some bike an your timing is right on the money. Check your magneto keyway if it's all good Im at a lose

hey i need help on timing my 86 xr250r, i just cant get it, i just put 3 brand new valves and i think i bent them thing is, i can have the flywheel on the T mark, and have my sprocket just perfect like yours, but if i rotate the engine 360 degrees to the T mark again, the lobes are up meaning the valves are open and making no sense since the valves cant be open when the piston is up

Hi the haynes manual say TDC MARK IS THE PUNCH MARK ON EARLY 250 MODELS

This looks good to me but like you I'm no bike mechanic! By-the-way most of us are one eye dominant so most people are right eye dominant so they sight a rifle with their right eye. The way for you to check is take a comfortable stance and hold your thumb out at arm's length with both eyes open lining your thumb with some object 20-40ft away. Keep your arm and thumb steady and close one eye at a time. The eye that sees the object in line with the object is your dominant eye, when looking through the other eye the object has moved!

Looks right on to me

Looks good, You got stumble fuxt.

Did you get it working yet? One of your comments stated that you put a timing light on the spark plug lead and verified that you are indeed losing spark. I don't think the magneto shifting in the key way would cause you to lose spark like that. It would alter the timing of the spark. If the key had completely sheared, the timing would be so far off, the bike wouldn't run at all. I think you should put a test light across the terminals of the coil. See if you are getting a pulse when the bike cuts out.

Looks good to me

Watching!

Idk. I’m lost right now too. No matter how hard I try I can’t get the marks perfect. I hop one tooth and it’s too low on the left, and go back a tooth and it’s too low on the right. It’s just slightly off and I don’t know why.

Ding Ding Ding I bet you found your problem! When a motor revs up it needs to advance the timing These bikes do that with the cdi Id bet it was out of time and when the cdi box advanced the spark it was already in the advanced position. If that makes any sense? Id bet had it been one tooth off in the other direction it would not have started at all. Hopefully it stayed put while you put it back together. Once you get the timing chain set just like you showed its a good idea to tighten up the adjuster so it all stays put. I hope you get her going with this.... now you may need to lean everything back out eventually and get it back to where the jetting was... good job

good video thanks for sharing

Looks to me like it's absolutely correct.

my lifters or valves are knocking on my 82 Honda xr250r idk what is wrong worth it does any one know

How do you loosen the timing chain

Ok im going to need your help if you want. So when i bought the bike it had 3 bent valves. So I bought 3 brand new valves and a new timing chain thinking that the chain had skipped a tooth. So I put it back together and it fired up once like 3 weeks ago. This afternoon i kicked over 2 hours and nothing. I did a compression check and I was very dissapointed to see 50 psi. I took the valve cover off to check my timing. It is still spot on but i must have bent my brand new valves since it has no compression even without the valve cover meaning all valves closed. So, I need someone to explain to me in details how to do the timing on this bike, what i did to time it, is find tdc, using the T mark on the flywheel, and then making sure that my lobes were down and that my top timing sprocket was aligned with the head (the 2 lines). The other thing is, I can have the motor on TDC and the valves closed (lobes down), then rotate the engine 360 degrees and have the vlaves open (lobes up) with the piston also being up since I am on TDC... which makes no sense since the valves can not be open when the piston is up...... anyways thanks if you read all the way here, if you cant help me just let me know ill set the bike on fire... lol anyways thanks.

How do you release the cam tensioner? Can't find any information.

aren't there 2 crank marks on those xr250r's? I'd use a paint marker and make sure there isn't 2.

I am stumbled by it.

What happens if it's not in time?

I have a 1986 XR250R. Picked it up for 400 bucks thinking it would be an easy fix. I have no bike knowledge what so ever but some mechanical knowledge. I ended up replacing cam shaft and timing chain, 1 lobe was trashed on the cam. put it ll back together by a junky ebay shop manual that wasant worth buying and still to this day it will not run. as far as timing goes I set it up the way you did and still no fire and not as much compression as I think it should have, also cheked for spark and fuel as far as I know. What should I do? willing to drag it out of the garage and take some pictures and start working on it again but I don't know were to start or whats wrong. Please help! thanks a lot.

I think it is either a bad ground on CDI box and or bad coil or CDI.

I need a camshaft for my 1984 honda xr250. Do you have one

I know this is an old video but I really need help. I have a xr200r the engine looks identical to yours I am trying to get the cam sprocket back on the cam but the chain seems to tight to get in on. Would you mind explaing what you did to get it on?

You did not say if you made sure that the valves had some gaps (loose) when you had it alligned at the TDC mark in the inspection hole. You might have been off 360 degrees, and should have rotated the crank counterclockwise one more turn (in order for the valves to be loose).

So, what was the problem?

Have you checked to see that the air filter is not plugged? Otherwise I don't know what to say.

Pro tip : Turn the can sprocket around so the lines on it face the same side as the flywheel timing mark (how it should be from factory) so you dont have to keep walking around to check them.

hey what year is this bike

Hi my name is bryce I have a xr 250 1979 and need a new air filter housing do you know where I can get it? I also would like to know where you got all of your wiring? To get ahold of me you can email me Jamie and Bryce Meek If anyone else knows this please email me.

Timing looks right to me but then again I know nothing about dirt bikes.

There should be marks I just did me ne

Just weld it back together and she'd be right guaranteed.

Need to cross your eyes when setting that TDC LMAO. Got an easy 6 letter fix for ya buddy... Y A M A H A lol.

He don't got a clue what he's talking about lmao