Air jets

[natemoen]

I can tell you this, because I tried it. The later model cab's air jets are a different thread than the earlier carbs. If you force the wrong jet in, it can bugger the threads.

The air jets in our carbs are just standard "small round" mikuni jets. nothing different about the different years. I have a set of '81 carbs and then my '78 carbs and the air jets are the same threads on both.

[airborneXS]

so i wonder where the 210's came in these...they appear the same in every way, tv said that the came off a 78, and from what he said, and everywhere else I've looked online, the 78 and 79's were the same, just different jetting....ive stripped the new set down ( NO BLOCKAGES AFTER LIGHT CLEANING!!!!!!!!! )

[cywelchjr]

so i wonder where the 210's came in these...they appear the same in every way, tv said that the came off a 78, and from what he said, and everywhere else I've looked online, the 78 and 79's were the same, just different jetting....ive stripped the new set down ( NO BLOCKAGES AFTER LIGHT CLEANING!!!!!!!!! )

As steve said, he's seen 78's with both size air jets. Over the years, both in and out of the military, I've seen multiple manuals with clear errors, in some cases with blatant ones that NEVER got fixed. Just because the manual says something, if observation over time contradicts the manual, then one must accept that the manual may well be wrong, and since third party manuals are virtually always make from the factory manual just designed to be more user friendly, they will usually have the same errors as the factory manual, and if nobody ever bothers to submit the error, it never gets fixed. And one explaination of seeing them both ways, could be that some folks finding the carbs with air jets not being the size specified in the chart, they may have changed the air jets to match the chart rather than leaving it as it came from the factory. At this point in time, it's something that we most likely will never know now.

[SFerinTEXAS]

I have also seen both. I believe the 210's were in a set of 78's. Ive thought it may have been due to the elevation of the point of sale destination.Dunno

[DGXSER]

After 30 years, who is to say what carbs were off what bike. The 78 and 79 were identical carbs, needle jets and all from what I have read, so who knows who put the 210s in for what reason, and if the carbs were originally on a 78 or not. Unless your the original owner, you are guessing at it.

At the end of the day none of it is going to matter to you Airborne, you most likely have a different setup than they were tuned and jetted for anyway. So now you need to find what works for your set up.

[Schming]

X2

After 30 years, who is to say what carbs were off what bike. The 78 and 79 were identical carbs, needle jets and all from what I have read, so who knows who put the 210s in for what reason, and if the carbs were originally on a 78 or not. Unless your the original owner, you are guessing at it.

At the end of the day none of it is going to matter to you Airborne, you most likely have a different setup than they were tuned and jetted for anyway. So now you need to find what works for your set up.

Start close to OEM setup, use the modded jet chart to get closer,carb tune/ color tune, do a proper throttle chop and READ your plugs.
You will find the "Seat o' da' Pants Dyno and a good ear along with the plug read yeilds the best results. YMMV