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What year is the bike and engine? What is the main problem area ?
TeeCat
One-Mik Wonder
Tuning is a very broad term, though. I think RG is wanting to know more about specific symptoms your bike is displaying. He's really great with diagnostics, even from a distance, but the more information he has, the better. Likely, he can help you narrow it down if you're as descriptive as possible with symptoms and setup.
TC
TC
to get into more specifics
the bike is a 76
it has a 750 big bore kit
straight pipes, ending just in front of the back tire
it has pod air filters
i started out with main jets size 125 and the needle set second slot from the bottom.
with these in it it would start and idle great but when i would start to open it up and hit about 4 - 4500 it would start popping.
i tried 127.5 and 130 sized mains and it did not help, i then moved my needle up 2 slots and tried this with 130 and back down to 125.
this is where i started to loose my patience because noting seemed to make much difference.
if i can provide with any more info please let me know, i had planned on a bike trip the end of this month and really wanted to take this bike.
the bike is a 76
it has a 750 big bore kit
straight pipes, ending just in front of the back tire
it has pod air filters
i started out with main jets size 125 and the needle set second slot from the bottom.
with these in it it would start and idle great but when i would start to open it up and hit about 4 - 4500 it would start popping.
i tried 127.5 and 130 sized mains and it did not help, i then moved my needle up 2 slots and tried this with 130 and back down to 125.
this is where i started to loose my patience because noting seemed to make much difference.
if i can provide with any more info please let me know, i had planned on a bike trip the end of this month and really wanted to take this bike.
Have you read the carb guide..................it is "must" reading for carb tuning.
click on "Tech" at top of page
click on Carburetors
.....XS650 carb manuals
....www.amckayltd.com/carbguide.pdf
I'm not a carb expert, but I can suggest a few things.
Popping probably means a lean mixture. Could be air leakage, mixture screw adjusted too lean, pilot circuit blockage, pilot jet too small, carbs not synced.
The 125 main jet would seem to be about right. The stock 25 pilot jet may be too small...........could try going up to a 27.5 pilot. Leave the jet needle in the stock mid position for now.
I'd recommend you do the "dead cylinder" adjusting of the mixture screws, starting at the 1.5 turns. If that adjusting ends up with the mixture screw a large amount away from the 1.5 turns, it means you need to change the pilot jet.
Follow that up with a carb sync using a manometer.
click on "Tech" at top of page
click on Carburetors
.....XS650 carb manuals
....www.amckayltd.com/carbguide.pdf
I'm not a carb expert, but I can suggest a few things.
Popping probably means a lean mixture. Could be air leakage, mixture screw adjusted too lean, pilot circuit blockage, pilot jet too small, carbs not synced.
The 125 main jet would seem to be about right. The stock 25 pilot jet may be too small...........could try going up to a 27.5 pilot. Leave the jet needle in the stock mid position for now.
I'd recommend you do the "dead cylinder" adjusting of the mixture screws, starting at the 1.5 turns. If that adjusting ends up with the mixture screw a large amount away from the 1.5 turns, it means you need to change the pilot jet.
Follow that up with a carb sync using a manometer.
