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Old 08-31-2011, 05:11 PM
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Goat Herder Goat Herder is offline
Gutter Rider
Join Date: Apr 2008
Location: N.M.
Posts: 6,251
Default Re: what did you do to your motor bike today?

Well I played for ever with my 21mm del carb . Got some gains in power here at 6000 foot. Took just one .005 shim out of my Centrifugal clutch from the stock configuration of ( ) ( ) ( ) ( ) ( ) ( / / / dropping the stall about 800 rpm's . Runs flawless late at night around about mebbe 2 seconds slower for a start to finish to full speed on a straight away. ''Night temp about 70 F. its a champ''.

With the big carb tuned in for this temp I could never cruise the bike slow again with out some kind of four stroking gurgle off Idle. If I tuned for that I lost my WOT tuning. Realizing that a touch of load put on a four stroke makes that gurgle go away. I did two things.

First one was I took my centrifugal clutch apart to service it. Found sediment accumulation built up inside the bevel washer stack. Cleaned it all up got a drop in rpm engagement of about 200 rpm's?

Road around and saw it helped but was not totally happy.

Took out the .005 shims was impressed. So I started to richen the carb up till it would 4 stroke again and then fine tuned that. I had ordered a leaner W7 needle to use in place of the stock W9 needle on the 21mm del carb as the W9 needle was on the top notch. ''clip''

Carb has a 55 pilot jet, 94 main jet 258 AU atomizer W7 needle at 3rd notch and stock slide. Whew wipes the sweat back.. Took a lot of time to get to this point!!

I can cruise the bike at 8 miles an hour now Feathering the attack on the clutch.

Here in the day today read at 101 F. outside ambient temp from my on board temp gauge and red lined clear across town got 316 F max motor temp but power is diminished on the big carb with changes in air density. It very easy to say it ran richer. .

I fine tuned for fall season weather. July tuning per-say would be a tad different but not by much with my currant configuration.. It don't take but a second to change out the carb's jet size. That would adversely effect temp too tho.

Id like to say in short all this tuning I have been doing is for absolute power. Moderation changes everything. I even have a barometric weather/temp gauge on my back porch. Just need The Barometric gauge on the bike too. lol

Except for the silencer thingy not sure what I was thinking there? I did make a air box from a 1990 GMC Serria pick up truck radiator return line. It so happen it was a spare old hose I had saved for ever. It also so happened it was the perfect diameter to clamp onto the back the the carb .

I use a short 7 inch or so section and simply stuffed the Foam racing air filter onto the back of that. Bike sounded really cool! Nice deep throughty sound. The tuning of the bike sourly agreed no bueno...

Observing this and the tuning properties it could offer? I then used a inch and a half ''total length'' elbow section from off the back of the carb and then the air filter.

After the carb fine tuning the clutch RPM engagement ditty etc I am happy to say the little cut in DB noise is very livable to me again. This concludes my carby saga finally!
Still gotta have a since of humor.
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