Mix & Match jet sizes?

[Anonymous]

How bad of an idea is it to mix and match jet sizes?

I just changed out the 110s on my '82 1100E, but the shop only had 3 each of the 112.5 and 115 sizes. So I took a pair of each and put the leaner ones on the outside. It seems to run nice & smooth, and about 20 degrees cooler.... I haven't re-sync'ed the carbs, either (no tool). Major other difference I have noticed is that it seems to pop a lot more on throttle off-deceleration or when driving at low rpms in 1st or 2nd. Other info - stock airbox and filter.

Reason I changed them is 'cause it has always run real hot and I pretty much know my way around the bike now.

Nick

[SqDancerLynn1]

The center two cyl are often jetted richer for added cooling Just ride it and see what the plugs look like

[Anonymous]

jets

I agree with lynn and for years have used a colder plug in the back cylinder on my HD, I am also going to put the same jets you are using in my 1000 115 to 17.5 and 120 in the center cause my center two cylinders come up lean on full throttle passes

[KEITH KRAUSE]

Before mixing jets, you should synch the carbs. If the vacuum is low in a couple of cylinders, those cylinders will run hotter than they should. Also check the ignition timing. Running the stock plugs?
Your decel' popping could be an exhaust leak. If it is carburetion, the popping at decel' and low rpm's in first/second gear wouldn't be caused by installing larger main jets. The mains take over at about 3/4 throttle.
For the popping, adjust the mixture screws out a little more. Maybe 1/2 a turn and test?

[Anonymous]

Thanks for the tips, folks.... I'll look for exhaust leaks and check the timing... I need to get my hands on a sync tool though. Oh, the plugs are stock, yes.

Nick