Engine issues...

[gsdapollo]

Hey guys, just got my bike back together and running and I hope im not having a major problem here. The motor ran fine before the build and I never touched it during the build. Just drained the oil and painted the motor. Just got it running on saturday and like any bike thats been disassembled and in pieces for 8 months I expected it to run rough for a little bit until at least any gummed up oil and gas burned off along with any contaminants that might have found their way in there. Anyways, the bike started right up, eventually it settled into a lower than normal idle, which I played with for a while and didn't see much change so i figured the pilot jets might be a little clogged. Ran the bike for about 10-15 minutes and that was it. My plan this week was to run the bike for about 5-8 minutes a day for about a week or so until she is able to warm up progressively (revs rise smooth and steadily with the choke on as she warms up) then idle smoothly and rev smoothly. Today she got pretty close to doing all those things although I noticed that only one header was smoking (i just wrapped and painted my headers so they usually smoke until they get broken in) I touched it and it is noticeably hotter than the other three. The motor seems to be running smooth, no weird top end noises although there is some very slight popping coming from the tailpipes. There is some smoke coming from the tailpipes but shes always smoked a little, not quite that much but I believe thats just old oil burning off. Also, the smoke coming from that header smells kinda of like burnt butter that you get when butter drips in a toaster, I believe this is the header wrap and it seems to be coming directly off the header and not from where the header meets the motor, but then again, since its noticeably hotter than the other three, im not quite sure. My thoughts are that Im just not letting the motor warm up enough for all the headers to have similar temperatures (by touch), or that something more serious is going on. Any suggestions or ideas? Thanks guys!!

 

[loka]

Have you done all the obvious things?

Checked plugs, spark
Carbs balanced
Timing etc..

I use an inexpensive infrared thermometer to gauge my header temp. When my pipes get past 300 d i stop using my hands.

JJ

 

[Wee Todd]

Rip around town the way it is,,,and kill some mosquito's

 

[gsdapollo]

Have you done all the obvious things?

Checked plugs, spark
Carbs balanced
Timing etc..

I use an inexpensive infrared thermometer to gauge my header temp. When my pipes get past 300 d i stop using my hands.

JJ

Ya I will be checking those this weekend hopefully if time allows, i just hope its nothing at all or just tuning related and not something like a gummed up or clogged oil passage causing that cylinder to run hotter than normal from a lack of lubrication. Or maybe its just me being paranoid... :-\

Rip around town the way it is,,,and kill some mosquito's

Ha, thats one way to know if you have problems or not...

 

[djelliott]

Just started breaking mine in with the wraps and yeah, they do have a funny odor. Sounds like that cylinder may be a bit lean. Mine was hotter on the right then the left and I just did what wee todd suggested. Seems to have evened out. I'm on a brand new motor build though so I gotta take it easy for awhile. I initially thought my pilot jets were lean until I pulled the plugs. At 2 1/2 turns out I'm WAY rich. Gonna dial them back in to 3/4 - 1 and read the plugs again.

 

[djelliott]

Ya I will be checking those this weekend hopefully if time allows, i just hope its nothing at all or just tuning related and not something like a gummed up or clogged oil passage causing that cylinder to run hotter than normal from a lack of lubrication. Or maybe its just me being paranoid... :-\


Ha, thats one way to know if you have problems or not...

Sounds pretty much like normal tuning issues. Believe me I'm be very cautious (paranoid) too. I did a lot of shit to this motor, port and flowed the head, lapped the valves, had a 3mm over bore done, KA cam chain slipper, tsubaki chain, barrnett clutch parts. There's a lot of margin for error. So far I've got a little over 20 miles on the casual break in and all I've found was it was rich at idle. Let's hope that's all. She is a freaking BLAST to ride BTW. I'm in love.

 

[crazypj]

You didn't actual remove the carbs and clean them did you.
Pilots are either clean or they are not. after 8 months, not would be my guess

PJ

 

[gsdapollo]

You didn't actual remove the carbs and clean them did you.
Pilots are either clean or they are not. after 8 months, not would be my guess

PJ

I removed them when I took the bike apart and covered the intake and exhaust openings with ceran wrap and rubber bands, but ya, it def felt like they were a little clogged, but shes idling much better now and doesnt bog off idle when given throttle so I think she just needed to clear her throat for a while, still strying to figure out that header part though... :-\

 

[gsdapollo]

Well I ran her again for about 7 minutes today and she ran perfectly. Started up in less than a second, warmed up smoothly with the choke, and idled perfectly with no stumbling when given throttle. The revs also dropped back to idle perfectly with no wandering or slow-to-drop revs like she was doing previously. So far looks like most of the bad gas has been blown out so its just a matter of checking the timing, carbs, plugs and oil and making sure everything is clean and good. That one header still seemed to be the only one smoking so I'll keep an eye on that as I go through and check everything else...

 

[Wee Todd]

Is this a rebuilt engine,,or a barn find., screw and adjust the motor to idle with fresh oil( 10w -30) let it spin in the drive way(1 hour minimum) then change to 10w -40,,,,,,,I do the same to rebuilds....seat the rings and dump the junk oil after an hour of idling

 

[boingk]

let it spin in the drive way (1 hour minimum)

You mean 10 minutes maximum, right? On an aircooled engine I would NOT want to be running it stationary for an hour - it'd probably hot-seize long before that.

Besides, after a rebuild I like to follow race instructions. Sure, dump that oil after an hour, but during that hour incrementally build your revs up. I use quarter throttle for 15min, half for 15min, then go a moderate run with full throttle interspersed with 3/4, and then a full-throttle run riding quite hard for the final 15min to bed the rings up top of their travel, so as to account for piston float. Remember to decellerate from top rpms as well to help ring seating.

Anywho, sounds like your teething stages are going well, gsdapollo. Let us know when you take her for the first ride hey? If you're really paranoid, you can get a small dry power fire extinguisher from any good automotive store. Carry it in a backpack until everything calms down. Hope for the best, prepare for the worst!

Cheers - boingk

 

[gsdapollo]

that had to be a typo, if i did that a smoking header would be the least of my problems lol.

Boingk - ya shes getting there. I looked at the old plugs and they were black so I need to lean it out a bit. I do have a question on timing though. I haven't done a compression test yet but last time i did one they were all pretty equal but down towards the lower end
of acceptable levels according to the manual. Is there ever a point where you might want to advance the timing some to make up for lost compression (again, its still within acceptable limits)? or am i completely wrong? Thanks!