Help needed - Poor Running & Lack of Combustion in #3 & #4 Cylinders

[Mach VIII]

Thanks all. I'll post up when I get the carbs off again (sigh).

 

Since I'm going to check the valves while I'm at it, is there a good source for the tool that's used to change out shims? Does anyone here have on that is loaned out to forum members or the like? I've got access to shims, but not the tool. Looks like I can purchase for around $60, but I'd rather not for a tool I'll likely only ever use once. [Edit - I'll start a separate thread about this to avoid hijacking my own thread, LOL]

Edited September 18, 2020 by Mach VIII

[Mach VIII]

UPDATE - I got the carbs off and a different shop went through them for me (that's a whole other story, and would've just done them myself had I known what all I would go through to get the done/back), finding a few potential issues.  The shop replaced the jetblock plugs, one of the jets, and a diaphragm while apart.  Nice guy and conscientious about his work, which I appreciated. 

The carbs are back on and I've done some tuning including carb. synch and adjusting the pilot screws.   Checking the plugs and adjusting the pilots further is getting it pretty good now, I think.  Pulled the plugs and #1 was wet, while #4 was kinda black and sooty.  #1 was not firing at idle.  Oddly, I had to turn #1 & #4 in almost all of the way to improve idle and get #1 to fire at idle and lower speeds.   After the tuning I ran a tank of gas through it and got around 37 MPH, with a lot of 70+ MPH speeds, but solo without any cargo.  Weeks later I replaced the plugs with a set of iridium NGK's and took it out for another test ride, this time getting 34.7 MPH on almost all 70+ interstate riding.  Both of these numbers seem a bit low from what I've read elsewhere on the forum, but others report similar numbers, so I don't know what to think.  I pulled plugs again the other day #1 is still a little wet, and #4 is better than it was before.  #2 & #3 look great.  In any event, it is running much better now.  I think I just need to put some real miles on the bike and see how it does.  Seeing as it was out of commission for at least a few years before I got it, getting some miles under it's belt would surely be good for it.

I even managed to adjust the valves and replace the front valve cover gasket while I had it all apart.  The bike has come together quite nicely as I've been finishing up my restoration.  Just finished replacing the fork oil, coolant, engine oil, and filter the other day, so now all of the fluids have been replaced.  I think it's finally ready to hit the road, even if it took me MUCH longer to get to this point than I ever anticipated.

Thanks to all who assisted in this thread!

[Marcarl]

If you replaced all the fluids, did you consider that brake fluid is also a fluid?

Sounds like you did a lot of work, something you can be happy about and proud of. Good going!!

 

[Mach VIII]

13 hours ago, Marcarl said:

If you replaced all the fluids, did you consider that brake fluid is also a fluid?

Sounds like you did a lot of work, something you can be happy about and proud of. Good going!!

 

Thanks!  No doubt it's a different animal than my Kawi ZX12R or my SuperMagnas, but I'm looking forward to some adventures with it.

Absolutely.  I de-linked the brakes and swapped the stock calipers for ones from an R6, so the brake fluid was changed as part of that process.  Clutch fluid was changed as well, since I had to rebuild the slave cylinder.  And to round out the category, I replaced the differential fluid as well, since I have no service history for the bike.