Main Jet Size???

[scty_p]

Hi Guys and Gals,

I'm rebuilding a set of carbs for a friend of mine. He bought the cheepo made in Japan kits rather than the Randakk kit I showed him and told him to buy. Regardless, these new kits have two separate main jets in them. One is 0.108 and the other is 0.125 and yes I had to get my daughter to read them to me. The kits say they are for '84/'85. The carbs are from an '85 Aspencade. I've looked in my manual, in Howard Halaz's book and scoured the website and others. What size main jet is the right size for this bike? Part of me wants to put the 108s in for the fuel economy, but the go fast part of me is screaming NOOOOO!!! USE THE 125s!!! Please help...

[scty_p]

OK, I just answered my own question, I think.

In the specs part of my manual (missed it the first time I looked), it says that the '84/'85 main jet size is #108 for 49-State and #125 for CA.

Any thoughts? Stick with the #108 or use the bigger(?) #125?

[bs175dths]

How good of a friend is your friend? Kidding!

I live in So. Cal. so I must have the #108. I didn’t look (couldn’t see) the number on the jet.
I think the performance is just fine, and the mpg is good.
I can’t believe the larger jet would have that much impact on either throttle response or mpg – nominal at best and your friend may not notice or appreciate the difference.
Ask your friend what he wants, giving him the benefit of your experiences, then let him decide.

Not using the parts you recommended is already one strike, deciding what jet he should use could be strike number two.
Doing a favor for a ‘friend’ may backfire so use caution.

I would suggest you note and mention anything out of the ordinary when you do the rebuild. Things like stripped or deformed heads on jets or float bowl screws are clear signs of previous owner abuse and you certainly will take the heat if things don’t work the way your friend may want.

I did a carburetor clean and adjust for my brother (not a friend but family) who had paid a ‘shop’ to do the job on his CB750.
WHAT A FLAMING NIGHTMARE!!!!!
I decided to stop telling him what I was finding because it was giving him an ulcer.
loose jets
abused slots in screws
one of the choke butterflies was severely out of round, warped and not seating properly
diaphragms not seated properly – sealed, but not seated properly
partially obstructed ports and jets
synch was way off!

When I returned the bike to him, he said he heard a bike coming down the street that kind of reminded him of his.
When he saw it was his, he couldn’t believe the difference in the exhaust note.
I told him to take it for a ride and as he let out the clutch, he couldn’t believe the response!
He was all smiles when he returned and said the bike had never run so good.

Doing ‘favors’ can backfire. Use caution and your own common cents (I know, it’s a joke)

I find it fun to help someone in need, especially if they are willing to learn.

~O)