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Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 10:58 am
by kmisterk
Kurt in S.A. wrote: Fri Jun 18, 2021 6:31 am

I notice in the ABC Airmail that a TechDay is coming up on August 21 in Tacoma at the Boxer Barn. Not sure how much wrenching will be going on, but might be worth a stop to get to know people...maybe even join!

Kurt in S.A.
I am actually paid members of both MOA and ABC! That's awesome, I'll have to look into that tech day! I'm not even sure where the Boxer Barn is, but I'll find out! Thanks for the tip on that one.
Rob Frankham wrote: Fri Jun 18, 2021 5:16 am Well, that explains the fouled plug then...

The 'slime' in the bottom of the air box is gearbox oil. The bolt loose in the box should be securing the airbox to the top of the gearbox (transmission on your side of the pond... ;) ). The threaded holes in the top of the gearbox is open to the inside so, without the bolt in place, gear oil can be thrown through the bolt hole to where it will get ingested by the air tubes. Gear oil is a very good medium for fouling plugs!

Replace the bolt and I'll wager that problem (at least) will be solved.

Rob
Any thoughts as to why it seemed to only affect the right cylinder?

Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 12:08 pm
by Kurt in S.A.
Well, if you're a member of the ABC and the MOA, you can look up the phone numbers of those near you and get their input. At least see if there's someone nearby that provide a second pair of eyes. The MOA has an Anonymous app that can be downloaded onto your phone so you don't have to carry the book around.

Kurt in S.A.

Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 12:22 pm
by kmisterk
Kurt in S.A. wrote: Fri Jun 18, 2021 12:08 pm Well, if you're a member of the ABC and the MOA, you can look up the phone numbers of those near you and get their input. At least see if there's someone nearby that provide a second pair of eyes. The MOA has an Anonymous app that can be downloaded onto your phone so you don't have to carry the book around.

Kurt in S.A.
Oh, this is great info! Thank you!

I'll absolutely be getting that app and reaching out to someone if I can.

Thank you!

Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 4:27 pm
by Rob Frankham
kmisterk wrote: Fri Jun 18, 2021 10:58 am
Kurt in S.A. wrote: Fri Jun 18, 2021 6:31 am

I notice in the ABC Airmail that a TechDay is coming up on August 21 in Tacoma at the Boxer Barn. Not sure how much wrenching will be going on, but might be worth a stop to get to know people...maybe even join!

Kurt in S.A.
I am actually paid members of both MOA and ABC! That's awesome, I'll have to look into that tech day! I'm not even sure where the Boxer Barn is, but I'll find out! Thanks for the tip on that one.
Rob Frankham wrote: Fri Jun 18, 2021 5:16 am Well, that explains the fouled plug then...

The 'slime' in the bottom of the air box is gearbox oil. The bolt loose in the box should be securing the airbox to the top of the gearbox (transmission on your side of the pond... ;) ). The threaded holes in the top of the gearbox is open to the inside so, without the bolt in place, gear oil can be thrown through the bolt hole to where it will get ingested by the air tubes. Gear oil is a very good medium for fouling plugs!

Replace the bolt and I'll wager that problem (at least) will be solved.

Rob
Any thoughts as to why it seemed to only affect the right cylinder?
At a guess, I'd say the right airtube is closer to the hole so it hoovers up more of the oil...

The other factor is that, whenever you check the plugs, the engine has been running on one cylinder so that cylinder will have tended to burn the oil off while, in the non running cylinder, it will have accumulated on the plug and not been burned off for probably several thousand rotations of the engine.

In any case, the bolt has to go back into place so give it a try... lets face it, you've got a plug showing extreme signs of oil fouling and you've got oil being introduced into the airbox... what are the chances that the two are unconnected.

Rob

Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 4:41 pm
by kmisterk
Rob Frankham wrote: Fri Jun 18, 2021 4:27 pm Let's face it, you've got a plug showing extreme signs of oil fouling and you've got oil being introduced into the airbox... what are the chances that the two are unconnected.

Rob
Yep. I basically was following this logic, I just wanted to get an understanding before assuming it was the issue. It's entirely possible that the bad running state it's in now, even if it's idling and running *okay,* is simply due to residual plug fouling. Another new set of plugs will be purchased today after all my maintenance was performed yesterday and I'll be sure to give it a good 20-30 mile ride before jumping to further conclusions about its performance.

I've purchased the pieces needed for a carb rebuild, save for a few of the metal pieces (essentially, everything listed in one of my early posts on this thread). I'll do that after I get some good run time on new plugs after the existing maintenance has been performed.

Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 5:14 pm
by Rob Frankham
Put the bolt in anyway... it needs to be there... it would need to be there even if it made no difference to the running at all.

Rob

Re: Carb Rebuild Planned For This Weekend

Posted: Fri Jun 18, 2021 5:16 pm
by kmisterk
Rob Frankham wrote: Fri Jun 18, 2021 5:14 pm Put the bolt in anyway... it needs to be there... it would need to be there even if it made no difference to the running at all.

Rob
Oh, yeah, I guess I didn't make that clear. The bolt was absolutely replaced and re-tightened down.

Re: Carb Rebuild Planned For This Weekend

Posted: Sat Jun 19, 2021 1:45 am
by kmisterk
So, an awesome end result!

After all the maintenance and tuning I managed to do last night, followed by new plugs today, I was able to put on a good 50-60 miles on the bike today, and it performed Flawlessly! So well, in fact, that I decided against rebuilding the carbs just yet.

I do have the kit for it, but I'm waiting to actually do the rebuild till likely end of summer, if it does not end up becoming needed before then.

Made yet another idling video after the new plugs went in and after about a 20-minute warm-up ride. Ahhh, this bike is so amazing.


Re: Carb Rebuild Planned For This Weekend

Posted: Sat Jun 19, 2021 4:45 am
by Rob Frankham
kmisterk wrote: Sat Jun 19, 2021 1:45 am So, an awesome end result!

After all the maintenance and tuning I managed to do last night, followed by new plugs today, I was able to put on a good 50-60 miles on the bike today, and it performed Flawlessly! So well, in fact, that I decided against rebuilding the carbs just yet.

I do have the kit for it, but I'm waiting to actually do the rebuild till likely end of summer, if it does not end up becoming needed before then.

Made yet another idling video after the new plugs went in and after about a 20-minute warm-up ride. Ahhh, this bike is so amazing.

Within the limitations of the microphoine, YouTube and reproduction distortion, that sounds pretty good. Glad you seem to have got the fouling issue under control... now ride and enjoy :D

Rob

Re: Carb Rebuild Planned For This Weekend

Posted: Sun Jun 20, 2021 10:59 am
by SteveD
Well done.Image

But that seat :roll: