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Did a rebuild but now wont start

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I just got done rebuilding piston,valves, and springs. The bike wont start. I think my problem is timming with the chain. When i was taking it apart i made a mark with a marker like everybody said on the chain and the gear. I put in back togeather with the mark i made. I took the chain tenshioner out so i was wondering if the chain can move or skip a gear down in the crank. It sounds like it wants to kick over but it wont. I know i put the valves it right and the springs too. Also the bike seems to have alot more comprssion that ever. Im possitive i put the piston and rings in correctly. What should i do. How would i know if the chain is off by a tooth down below, is there a mark or something. please help

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Check the timing marks on the inspection cover on the clutch side and the marks on the cam gear and head. The manual covers this.

It can skip a tooth on the lower gear.

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the bottom inspection hole behind the cap with the hex in it has two gears you can see theirs a dot on each line them up.

your cam sould be lobes up and your cam wheel on the end of the cam has two flat lines that should be perfectly parallel with the top of the head you can bet your out a tooth. recheck this then kick your bike over slowly a couple of times and then recheck before you put the valve cover back on.

easy peasy.

thiers apost on this site somewhere with pictures that will be of value to you if your still unsure.

good luck

:)

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thiers apost on this site somewhere with pictures that will be of value to you if your still unsure.

It's a sticky thread on the top of this forum.

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Make sure the cam chain is on the lower gear.I just got done with a rebuild about 2 weeks ago and it happened to me.My fault.

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I just checked and the lobes are facing backwards and the lines on the gears are lines up to where the top of the case is. and the t mark down by the cluch is lined up. How will i know if the chain is off the gear down below in the case. do i need to take the whole left side cover off.

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when you you kick the kick start do you feel some pressure come out of the silencer.if yes it is fine if no it is probally off.

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Well Ive never rebuilt one before but id have to say the easiest way would be to pull the valve cover and slowly turn it over and see if the chain starts to move, then you know its on both gears. While your in there slowly kick it over and visually see how the valves are working. I would hold down the shut off button while kicking it over to check things, theres not much if any chance it could start kicking it over slow like that but id rather be safer than sorry.

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There is compression coming out the pipe but its really hard to kick. I bet it got off a tooth in the lower gear. So how do i get in there to change it and what do i need to look for. is there some kind of mark. Some body has to know. i dont want to take it to the shop. Is ther any way i could have put in chain tensioner in wrong or backwards.

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There is compression coming out the pipe but its really hard to kick. I bet it got off a tooth in the lower gear. So how do i get in there to change it and what do i need to look for. is there some kind of mark. Some body has to know. i dont want to take it to the shop. Is ther any way i could have put in chain tensioner in wrong or backwards.

The chain may not be "Off a tooth" so to speak but it may have got a loop of chain down there so there is an extra tooths worth of chain hanging around down by the crank sprocket. But usually when that happens and you roll the motor over it will correct itself. But by correcting itself it will throw the cam timing off so you have to recheck it again. Roll the motor over several times then recheck your timing. That is my advice.

That or turn the gas on :)

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If i keep kicking it over you say that the chain down below will atomaticly realign itself. i dont think so. but ill try.

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If i keep kicking it over you say that the chain down below will atomaticly realign itself. i dont think so. but ill try.

Unless the chain guides are so tight against the chain that it cant pop past them I think it will.

Think of it like your rear sprocket. If you wrap the chain around it but pull a small loop of extra chain about half way around the sprocket. As you turn the wheel the extra loop will roll off the sprocket and right itself. At least that is how I see it.

Like I said unless the chain guides are preventing this.

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If the chain is on and you say the timing marks line up with the lobes facing towards the back then it should start.Make sure your at tdc.Open the cap that shows timing gear.Make sure marks line up then the marks on the cam gear should line up with the head (there are 2 marks) with the lobes facing towards the back tire.This is the proper timing setting.

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>Is ther any way i could have put in chain tensioner in wrong or backwards.

Note - most people call the small metal assembly that bolts to the side of the cylinder the chain tensioner. It's not the chain tensioner. The chain tensioner is the flexible black plastic piece that fits inside the cam chain tower and pushes against the chain. The metal assembly is the tensioner lifter assembly. See the Honda parts manual for part names. I suppose it will continue to be called the chain tensioner, anyway.

You can check the "chain tensioner" as follows:

Page 8-9 of the Honda Service Manual, '04 & '05 XRF250X, shows:

Remove the cam chain tensioner lifter bolt and sealing washer. (Rick's note - this is the 8mm-head bolt in the center.)

Turn the cam chain tensioner lifter shaft clockwise fully and secure it with the special tool. (Rick's note - use a small screwdriver and hold it in place with a pair of vise grips attached to the screwdriver handle - let it hang.)

Rick's note - Now, with the spark plug removed, but connected to the spark plug lead and the plug grounded to the frame or engine so the electrical system doesn't get a stray zap, kick the bike through slowly with the kick starter. The engine should turn over fairly easily.

If the engine turns over easily, you probably had the tensioner lifter assembly extended when you installed it and it was binding up the cam chain excessively. If the engine still does not turn over easily, you have another problem.

>How would i know if the chain is off by a tooth down below, is there a mark or something.

The alignment is done at the top; the lines on the cam gear aligned with the cylinder head surface. The lower gear has no alignment marks. You only need to get the alignment correct at the top.

Of course, the crank gear must be aligned to the index mark on the case (inspection hole near the clutch) and the piston must be at TDC on the compression stroke.

Someone wrote:

The chain may not be "Off a tooth" so to speak but it may have got a loop of chain down there so there is an extra tooths worth of chain hanging around down by the crank sprocket.

----------------------------------

This is not possible if the cam chain is over the cam gear; there is not enough slack for a loop or excess chain anywhere.

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Take the cover of the left side and be sure the chain is on the crank gear. There is a little metal tab under the gear to keep the chain on the gear but if you rolled the crank with slack in the chain it will come off and lodge between the gear and tab. While your in there check the screen in the lower rear of the case and clean it. Be careful putting the cover back on as there is a seal in there that seal on the end of the crank to provide oil pressure up top. Let us know what you find.

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Here's an idea. Take it to your local shop and have it looked at before you blow up your brand new "rebuild job".

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I have all the timming marks lined up. And the mother wont start. I accidently was trying to start it with the chain tensioner thingy out and it almost started. When i put the tensioner back in it had like doubble the compression. Also i checked my valves at TDC. My exhausts were in speck but my intakes have no space to put any thing under. If my intakes went to zero wouldnt it have like no compression. I cant think of any thing else. I drained my carb, new plug, and there is oil in it. I have gas too.

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You're installing the "chain tensioner thingy" incorrectly. If you had done what I advised, you'd be done now.

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It is super easy to make sure you have the timing chain on the correct teeth.

Pull the valve cover off.

Pull the spark plug out.

Place a long screwdriver down the plug hole.

Slowly turn the motor over w/ the kick start until you are at exact TDC (doesn't matter what stroke you're on.)

Now look at the hash marks and they should be EXACTLY lined up w/ the top of the head. (Again, doesn't matter whether the cam lobes are pointing to the back or front, because 180 degrees later you will be at EXACT TDC again)

If the marks aren't lined up, just remove the cam holders, tilt the cam down, and move the sprocket to different teeth, so that the hash marks line up.

Man, I wished I had figured that system out myself, it's brilliantly simple.

Pete

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