Bonneville America Forums Forums Technical Forums Performance Mods fuel problem

Hey Fella's just got home from summer drilling and got my america out for a scoot and the ****** thing starved for fuel at 100mph , I like the air up there ... the carbs were rejetted to 135's I have a norman hyde high flow air intake K&N filter the bike run's a little jerky a low speeds like it is starving for fuel , I had put fuel stablizer in before I went to work 90 days ago and on the way home today put some fresh fuel in but it is still running rough , weather was foggy and rainy but not to cold .. fuel filter maybe ?? what are your thought's

I'd disassemble the carbs n clean them out...I'd say after sitting 3 months without being ran combined with stabilizer in the fuel they just need a good cleanin out.


I'd also pull the petcock out of the tank and clean the screen on it as well.

well I am just heading down to the shop to take a look at this it is the first time in five years that I've had a problem with stablizer in the fuel bike usualy fires right up and runs fast and smooth ....

problem resolved , the carbs were set up with an UNI air filter in , I switched to the K&N and didn't re adjust the carbs ... I put the Uni back in ( heard this voice from the past , high school shop teacher what did you f*** with now , he was a dispatch rider in the war I rode an 850 norton chopper ) and she is running great in the rain had it up to 70 MPH no problem ... thanks for listening

So you switched from a UNI filter to a K&N filter and it changed the way it ran? I did the same thing and thought that maybe I was imagining that it did not run as well. So did you just adjust air mixture or did you rejet?

the carbs were rejetted 135 mains 45 idle with 1mm shims at the time I had the UNI filter in swapped out the stock snorkle air intake for a norman hyde high flow changed the stock petcock to a pingle high flow and the bike was running great ... in the spring the pollen was plugging up the uni it had to be cleaned every 2000 miles so I ordered the K&N the bike ran a little lean at high speed but since I have come home with the colder air the bike was running terrible so in the spring I will get the carbs re adjusted with the K&N filter in ... another buddy of mine on this site reminded me he had to increase his fuel by 5.5 turns to get his bike running good after putting a K&N filter in ... So it is not your imagination more air is going to require more fuel just have to get the balance right

5.5 turns? should maybe go up a size on the main jet

Wow, 5.5 turns. Never heard of anyone doing that. Be careful they don't fall out. If that's the case, you need to go up at least one jet size. Usually 3 to 3.5 would be considered max or where you need to increase the pilot jet size.

Not sure if this is what he meant but he said increase by 5.5 turns! so that would be in addition to the original setting. Starting from a lightly seated needle I don't like to go much beyond 3 turns, like stated above 3.5 max. After that up a jet size and adjust again.

well that was Nick Lowe in England that was saying he did that ( teck vault tick over problem) ,he just got me thinking ... like I said switched back to the uni filter bike is running fine ....I'll put the K&N back in next spring and adjust the carbs then , right now I just want to roll up some miles before I head back to the bush