Bonneville America Forums Forums Technical Forums Performance Mods Another jet question

I finally managed to crack into my stock carbs. I pulled out the main jet, and saw that it's a 120. Is this the stock jet? Also, I tried to get the pilot jet out but that thing is stuck in there good. Any tips?

Pull the carbs off and turn them upside down on a towel or something soft to prevent scratching the caps. Then use a screw driver that fits the jet very well and use a lot of pressure. If that doesn't work you can put the screw driver in the jet and tap it lightly with a hammer a few times then try turning it out again. I hesitate to suggest this but if all else fails put them in the oven to warm them and try again. Be careful if you end up heating them, A) don't want to get them too hot and B) don't want you to start a fire in your oven! Most of the time turning them upside down for more pressure does the trick.

Depending what year you have that is the stock jet, you probably have the stock 42 pilots too. I have heard of later models having different jets from the factory.

In addition to what Ian wrote above I have found the key to replacing a pilot jet to be: (1) pull the carbs (2) use a driver blade that fits the jet slot as exactly as possible & (3) "crack" it loose with pressure & a sharp twist (impossible for me to do without pulling the carbs)...

I have been able to change them with the carbs in place but have also had a stubborn one that required pulling the carbs. I had one that I had replaced not long before I need to do it again and one of them was still stubborn and I had to pull the carbs. That jet had only been in about a week too.

My '03 had 120/42 jets stock.

Looky here...
Pat's carb site

Why aren't the Bonnys fitted with 120/42? It appears they are somewhere around 110/40 (Not sure)? They put out more power yet have leaner jets.

My 03 had 120/42

I too was able to change the pilot jets without removing by again selecting a well fitting screw driver and ensuring it is held up tightly with one hand, using a pair of pliers to loosen or crack open the jet. It worked well for me and in fact I've never had to remove my carbs. Probalby just a bit of luck involved there

That is possible but if he has already tried the brass slot is probably buggered a bit making it even more difficult. I advised removing the carbs to prevent making it so bad it wouldn't come out at all. In my case I had to remove mine because the brass slot did indeed give way making it impossible to do on the bike.

I don't think I've dented the slot at all. I was using a very long thin screwdriver (usually used for electronic work) and it felt like the shaft would break before the jet would turn, so I stopped. I didn't feel it shift at any point. I need to get the same size screwdriver but with a beefier shaft. (heheh - he said "beefy shaft"). Then I'll try again.

If you can get that good of a bite on it then there would be no reason to pull the carbs to make the change.

Maybe it's not clear, the carbs are already off the bike.

The previous owner had a set of racing carbs on there. I took those off, and want to refit the stock ones. Before I do that, I want to make sure the right jets are in there.

AH! Now I understand how you got the long driver in there and got such a good bite!

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Maybe it's not clear, the carbs are already off the bike

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Was that a maybe?