Hard starting - decompression troubles ?

My XR600 with the 630 kit on it has become a bitch to start cold. It used to start hot or cold near first kick. I noticed my auto decompression unit does not appear to work compared with other 600's. I have always used the manual one to get it into the TDC and one good kick would be enough. Valve clearances are correct. Any one out there with any ideas if the decompression system not working could cause the hard starting :excuseme: problem ?.

My XR600 with the 630 kit on it has become a bitch to start cold. It used to start hot or cold near first kick. I noticed my auto decompression unit does not appear to work compared with other 600's. I have always used the manual one to get it into the TDC and one good kick would be enough. Valve clearances are correct. Any one out there with any ideas if the decompression system not working could cause the hard starting :excuseme: problem ?.

is it harder to kick over? bad fuel?

Same to kick from TDC but impossible to push through compression without the manual decompression lever.

If it used to start easily, but now gives you problems, something must have changed.

Do you have the stock or an aftermarket cam? Many aftermarket cams do not have the auto decomp system.

For me hard starting was a symptom or worn out parts. Valves that leak or shot rings. However, there are a few other things which can cause these starting issues. First is the carb. Clogged passages, clogged jets, and changes in the float level can causes hard starting. Another possible problem area is the ignition. Weak ignition usually shows most at starting, because the engine is turning so slowly. The stator is usually the part that fails, but all of the other components can fail as well. Even the wire from the coil to the plug can cause problems.

I have a similar question, my 2007 XR650R starts way harder than my 03 XR650R. Of coarce it only has 58 Miles on it, im quessing its got so much compression due to the brand new motor? If the decompression is not used there is no way to start it cold unless you put the kickstand down and stand up on the pegs!

cable adjustment?:excuseme:

My 95 600R is actually pretty easy to kick through without the use of the manual lever. In fact, I only recently even put a lever and cable on it. For some unknown reason the guy I bought it off had removed it, he said "ah you never need that because it's got auto decompression". I kept it that way for a year and although it was a pain to start when cold, I could always kick it over.

Still, it's nice to have the lever for flushing it out when I drop it.

The Honda manual has a schematic and explanation of the auto system at the back. I've looked at it but still only vaguely understand how it works.

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