HONDA Xl600Rmg 1986 will not start issue

[wego21]

Hello all,

I have got a Honda xl600Rmg 1986 for free from one guy, he said it has issue with electric circuit only. I have fixed and changed all the parts and that's ok now. I have cleaned the carbs 2x, I have checked the valve clearances and spark. I have not disassembled the head to check for bent valves or correct timing marks, but I have checked the timing and clearances with endoscope and it looks properly aligned.

ISSUE:
When I try to start the bike it turns over, seems to be willing to start, but it will not keep running. As soon as I release the starter button it will die. It gives also a strange noise and some time seems to back fire through the carbs.

I have recorded a video as well https://youtu.be/ormnxFSKn30

If you know what's wrong please help me out

[Meatybeaty]

First I would pull the spark plug and see what condition its in (wet or dry)

[Easy-X]

[Nobby the Bastard]

How do you check clearances with a endoscope?
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[wego21]

[Nobby the Bastard]

Did you check that the lobes on the cams were opposite the valve when you checked each one? I don't think putting it on the timing mark is correct.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Fizzer Thou]

A friend used to own one of those 600s and the twin carbs are a PITA to set up.What we found in the end was that the seals between the cylinder head and particularly those numbered #14 in the attachment,were perished.We then went on to find that the strangely shaped one #15 was also damaged,but not as badly as those directly affected by the heat from the engine

https://www.cmsnl.com/honda-xl600rm-1986-g_model50184/partslist/0082.html#.XbxsiLiaLTQ
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Just talk bikes.What else is there?

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[wego21]

[wego21]

[Meatybeaty]

[wego21]

[Nobby the Bastard]

There are two tdcs for a single rotation of the cam...
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Suntan Sid]

What Nobby said is correct!
To check the timing on the XL both cam lobes must be pointing 45 degrees upwards, if they're not pointing up you are not at TDC on the compression stroke, you are, effectively, 180 degrees out.
Removing the tappet covers will allow you to check this!

Also, have you checked that the decompressor is operating correctly?
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"Everybody needs money, that's why they call it money!"

[Shaft]

[Meatybeaty]

[wego21]

[Meatybeaty]

Have you tried with the kickstart?

[wego21]

[Kawasaki Jimbo]

[wego21]

[bikenut]

cvompression test ?

clean plug and choke working properly, the sprung loaded flap....
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nuts about bikes

[wego21]

[Nobby the Bastard]

[Robby]

I also owned one of these a few years ago. As Shaft said, the electric start on them is useless.
Don't even try without a fully charged, fairly new battery. New battery cables can also help, as can stripping down and cleaning the starter motor, and replacing brushes.
I used to just use the kick start. Not a particularly easy bike to kick start either, but more effective than the electric start.

For general diagnosis now, and just to get it running, spray some easy start into it and see if it works.

[ssray]

The last single I had that was a pig was down to the pilot screw being in too far, check its current spec
Had it been standing? Carbs been cleaned?
New plug and easy start, fully charged battery or connected to a non running car battery to allow for a few different throttle openings, ie if its trying but not starting then give it wide open throttle for a bit then return to normal
Only turn over for 10-15 seconds at a time