Starting/running problems

[dswalker]

Hi guys, been a while since I've been on here but once again I require your sage like advice.

My 92 Sp has been stood for a couple of months in the back of my garage, I pulled her out the other day to get her MOTd for the summer. After fixing a couple of known issues, like adjusting the float heights and mix screws, I tried starting her up. She did start but instantly wanted to rev to the redline so I hit the kill switch. I have no idea why she's doing this.

Since then I have tried everything I can think of, I have:
Replaced all o-rings with the exception of the main jet holder as I don't have any that size lying around.
Cleaned the carbs, all in good condition, slides move freely, needles in correct position.
Ran fuel system cleaner through the carbs
Checked the plugs, they were black so I gave them a quick clean and check and they are sparking fine outside the cylinders.
Coated everything in damp start to check for air leaks, none were evident.

After doing all this she now won't start at all. In all of this I haven't re-adjusted the float heights but I am considering it but I don't think it will help as (so long as I've done it right) they are all set back to 20mm.

During the process I have had her back-fireing from the exhaust and through the carbs, at one point after spraying some WD-40 into the bore of number 1 cylinder she idled at 6000RPM but that wasn't for very long and, as I said, she isn't starting now.

Thanks for reading and any suggestions are very welcome.

[dswalker]

OK got her started but she still makes a break for the redline every time.

I've now changed the oil and plugs, just to be sure and have had the carbs apart again but still no luck. I'm starting to think that a seal in the engine has either dried out or that something has become blocked. Any suggestions about where to start?

Thanks as always.

[ben2306]

mine was also high rev to high rpm once started after i did my carbs. after another 2 times of looking @ the carbs, it also didnt managed to start anymore. tow to workshop and they got it right back for me. for mine, should either be throttle cable or carbs only, nothing to do with engine or spark plugs etc cos he only charged me labour for service carbs. as they only took 1 day to sort it out. but as i was too happy, never asked how he did it. hope it helps...

[ben2306]

recently i've changed the pick up coil as it was faulty. maybe you can try test it, see whether its faulty too.

[dsr91]

Was there ever a out come to this , my bike seems to have same issue