Fuel mix screw
Fuel mix screw
Why is this screw capped? I guess I can understand why the factory would cap it on a new machine, but sooner or later it would be needed for adjustments to compensate for age.....right? Can it be removed with carb still installed? Thanks
Ultimate HDF Member
Joined: Jul 2011
Posts: 5,477
Likes: 5
From: New Braunfels, Texas
Usually if it is still plugged there is a chance it was never rejetted. You can take out the plug and rejet with the carb on the bike but it is more challenging. Again, if you need help, it's 45 minutes away. Let me know.....
Supporter
Joined: Jan 2007
Posts: 15,788
Likes: 5,621
From: along the shore of Mishigami
There is a way to drill while on the bike. Using a long 1/8" drill into the very bottom of the screw housing, from the side, just enough to get thru that thin housing, then pry the cap off. Turn in the screw till lightly seated then back out about 2 1/4 turns, that's a base adjustment, your bike could vary once it's hot. I adjusted mine till I got the carb farts, then out till the fart's disappeared. i installed two #4 brass washers under the needle and kept the original jets installed. Some use a 1988 Sportster needle. This aids in the transition between idle and throttle application.
Rather than fool with the local dealer parts guys, I looked for/purchased a complete kit from CV Performance. Kit has all the right parts and an external fuel-mix thumb-screw to replace the OE piece. This way I'll know what is what in the carb and not have to guess at what was/was not done before I became the owner/head-wrench/maintenance guy. Thanks
Road Master
Joined: Nov 2010
Posts: 1,115
Likes: 69
From: Bay Area, NorCal
Not trying to make your project any harder, but since you'll have the carb off it might be worth the extra time and $ to swap out the manifold-to-head gaskets at the same time - they go bad after a while and start to suck air, making carb adjustments/proper tuning highly difficult.
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Not trying to make your project any harder, but since you'll have the carb off it might be worth the extra time and $ to swap out the manifold-to-head gaskets at the same time - they go bad after a while and start to suck air, making carb adjustments/proper tuning highly difficult.
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Got carb off and took it apart. Someone had been there before. Had a #48 slow-jet and a #180 main-jet. Stock are 45/190. Kit recommendation is 48/195 so that's what I put in along with new needle. (kit also came with a 46/190). Slide vacuum port had been drilled to 1/8". I'm going to see about changing the manifold seals tomorrow, drain the gas tank, and then put everything back. The thumb-screw idle mix screw will come in handy.