Strange SOBoxer behaviour
in [Classic Motorcycles]
|
Prev: Nice looking 400 Four
Next: Out on the 400 Four
From: Steve H on 23 Jun 2010 17:25 The Older Gentleman <totallydeadmailbox(a)yahoo.co.uk> wrote: > It does sound like it's running lean. Do a plug chop, at varying > speeds, > to see whether it's needle settings or main jets. At this point I think I should get a man in.... > Two other possibilities: what oil grade are you running? Try a 10/50 > or > a 5/50. Generic car oil.... As it's what I had in the garage, so not one of the above. > Secondly, It does have an oil cooler, right? Yes. -- Steve H
From: Pip Luscher on 23 Jun 2010 17:42 On 23 Jun 2010 20:33:45 GMT, Steve H <italiancar(a)gmail.com> wrote: >Any suggestions? My thoughts are that it appears to be running rich, and >has sooted up the plugs? Pops & bangs usually mean lean mixture or air leaks downstream of the throttles. Running hot suggests the same. There isn't a balancer stub screw that's fallen out is there? If the throttle's closed then the intake depression is at a maximum so it would draw more air through a leak at idle or on the overrun, which might explain the poor idling. A bit of choke might help diagnose that - if it helps the idle then it's another pointer to a lean mixture. You can get pops due to exhast leaks at the top of the pipes but I wouldn't have thought that it would make it run so lean that it ran hot. Besides that, obviously you'd hear it blowing. -- -Pip
From: The Older Gentleman on 23 Jun 2010 17:49 Steve H <italiancar(a)gmail.com> wrote: > The Older Gentleman <totallydeadmailbox(a)yahoo.co.uk> wrote: > > > It does sound like it's running lean. Do a plug chop, at varying > > speeds, > > to see whether it's needle settings or main jets. > > At this point I think I should get a man in.... > > > Two other possibilities: what oil grade are you running? Try a 10/50 > > or > > a 5/50. > > Generic car oil.... As it's what I had in the garage, so not one of the > above. > SOBoxers are remarkably susceptible to oil grades, especially in hot weather. I strongly suspect, now, a combination of wrong oil and carb/mixture gremlins. -- BMW K1100LT Ducati 750SS Honda CB400F Triumph Street Triple Suzuki TS250ER GN250 Damn, back to six bikes! Try Googling before asking a damn silly question. chateau dot murray at idnet dot com
From: SpamTrapSeeSig on 24 Jun 2010 08:29 In article <809332112299021051.489530italiancar-gmail.com(a)news.individual.net>, Steve H <italiancar(a)gmail.com> writes >The Older Gentleman <totallydeadmailbox(a)yahoo.co.uk> wrote: > >> It does sound like it's running lean. Do a plug chop, at varying >> speeds, >> to see whether it's needle settings or main jets. AND check the carb diaphragms for splits and pinholes, etc. I know I mentioned this recently (it still hurts!), but one of mine went, and I had a lot of expensive valve work on that pot as a consequence: instant lean-ness, hot cylinder, scorched exhaust valve, seat and guides. -- SimonM ----- TubeWiz.com ----- Video making/uploading that's easy to use & fun to share Try it today! (now with DFace blurring)
From: Hog on 24 Jun 2010 09:53
The Older Gentleman wrote: > Steve H <italiancar(a)gmail.com> wrote: > >> The Older Gentleman <totallydeadmailbox(a)yahoo.co.uk> wrote: >> >>> It does sound like it's running lean. Do a plug chop, at varying >>> speeds, >>> to see whether it's needle settings or main jets. >> >> At this point I think I should get a man in.... >> >>> Two other possibilities: what oil grade are you running? Try a 10/50 >>> or >>> a 5/50. >> >> Generic car oil.... As it's what I had in the garage, so not one of >> the above. >> > SOBoxers are remarkably susceptible to oil grades, especially in hot > weather. I strongly suspect, now, a combination of wrong oil and > carb/mixture gremlins. Well, they do get very very hot in those conditions. As it is so easy, if you have a strobe check your ignition timing is spot on. Clean the float bowls, balance the carbs and do the valve clearances. But first of all throw the plugs away for some new NGK's. -- Hog |