Keihin carburetors

[tall-mike]

say hey xtrider; there is no stumble what so ever, until the last 1/4 twist of the throttle...then it's like you've hit a rev limiter and the motor shuts down . A little aggravating because it runs so strong until then. I truly welcome any ideas - theories on this matter. Thanks Mike

[tall-mike]

Ok...So the speed shop and their dyno has a three week back log ( Alba Racing ) . I could ride the bike as is , or I could pull the carbs and use my new found internet knowledge to really dick up these carbs. ( Raise float level , raise needle and find a useable main jet.) I think I'll drink on it tonight...( a twelve pack of cheap beer and internet poker) ...and decide tomorrow. Mike

[Rich]

Have you checked what voltage you have at the coils? Could be a coil / plug problem.

[tall-mike]

Hey Rich, The answer is no, not because I don't want to , but I am ignorant of the process. I rode the bike today, had a nice ride. Started with one kick, and as long as I rolled the throttle on slowly, it didn't bog down. Going through the gears ,shifting at 3 to 5000 rpm it cruises along at 75 mph with no bogging down. I am using less than half throttle in doing this. The throttle response is excellent. It just seems I am leaving a lot still on the table with these carbs, because I'm not getting any use of the Main jet. Possibly raising the float level, the needle and installing the proper main jet everything will get sorted out. Maybe I need a fuel pump because the bowls are running dry. I don't know. But eventually I'll have these carbs working at their optimum level. I'll just pay a professional tuner to do it. Mike

[tall-mike]

Nix that last Idea, speed shop wants to have the bike in their shop, just sitting, and won't work on it for two to three weeks.This sounds a little nutty to me. So this weekend I'll adjust the valves, and raise the needles on the carbs. The spark-plug shows it's running lean. I've e-mailed Wayne.gum@erd.co.nz about purchasing one of his hyper pac CDI units. And on reassembly I'll make sure I don't have any vacume leaks. If no joy after this exscursion I'll find a shop with a reasonable wait time...Mike

[ActionManMelb]

Hi Mike, you could always do it yourself!!!

Read this thread on our forum and click on the link within.
Very nice wide band o2 sensor with display. Tuning made easy. Use the road as the dyno.
Cheap and made in your own country.

Get to it and let us know the results.

[tall-mike]

Thanks for the link Action Man, checked it out, did the math, and found a dyno shop which will do the work for a hundred dollars more with no long wait. I'll post the results. Thanks Mike

[xtrider]

I'm looking at that myself. The amount of motors I've tuned (or tried to), it would be well worth it.

[tall-mike]

For an experienced mechanic the air to gas ratio takes all the guess work out. The flat rate for dyno and adjustment is 300 bucks plus parts. So for a hundred bucks extra, I get the carbs professionally dialed in. I would of spent that on extra needles , jets and having a bung welded to the exhaust. A bargain in my book. Mike

[xtrider]

I'm talking about doing several bikes/quads in a year, I can weld bungs myself so to take it somewhere else wouldn't pay for me. To do just one bike, ya it would be costly.