The power of the airscrew.
Posted October 27, 2000 - 08:12 AM
Posted October 27, 2000 - 08:52 AM
Just a heads up. The air screw you are referring to (on The bottom side of The carb) is really a fuel screw.
Posted October 27, 2000 - 09:34 PM
[This message has been edited by Boit (edited 10-27-2000).]
Posted October 27, 2000 - 01:41 PM
Posted October 27, 2000 - 02:15 PM
Are you SURE you don't have an OBDKP needle??
If you did have a DKP the top clip would be equal to a DVP 5 clips lower.
DKP#1 equals DVP#6.... a rich situation needing a lean pilot setting, matches what you have done.
The Yamaha parts fiche is wrong for the YZ426 and lists a DVP where the part is actually a DKP. Look carefully at your needle. This would explain it.
[This message has been edited by James Dean (edited 10-27-2000).]
Posted October 27, 2000 - 06:43 PM
I use the following setup
180 main, 48 pilot, 100 air jet, YZ timing, DVP #4, DSP pipe and header, airbox lid removed, about 1 3/4 screws out.
If you truly have a DVP needle, I can't even imagine how your bike runs, let alone running rich.
Posted October 28, 2000 - 06:20 AM
Posted October 28, 2000 - 06:54 AM
Posted October 28, 2000 - 09:56 PM
It will be interesting to see whether your jetting will be way off now or if something else is also causing problems. Be sure to check float level and all the passages such as pilot air jet.
Posted October 29, 2000 - 07:17 AM
You said 'no discs" are you running the end cap? White Bros recommends you run the discs (8-14) for optimum performance. I think from discussions on this board, most of us are running between 8-12. 8 if you need the bike quiter and 12 if you don't.
86TT225, 98CR80, 99WR, WR timing, throttle stop trimmed, air box lid removed, White Bros head pipe, silencer and air filter. Odometer and headlight removed. Moose hand and mud guards. YZ stock tank and IMS seat. Renthal Jimmy Button "highs" and Renthal Soft half waffle grips. AMA, SETRA.
Posted October 29, 2000 - 07:44 AM
Posted October 29, 2000 - 12:26 PM
Posted November 04, 2000 - 08:09 AM
Posted November 04, 2000 - 09:22 AM
run a regular hose
Posted November 04, 2000 - 01:20 PM
Does this only happen at 1/4-1/2 throttle. This indicates clip position. There is always the possibility the needle was mislabeled or mismanufactured.
If it is rich below 1/4 throttle it is probably the pilot circuit giving you trouble. Maybe choke too. Your pilot screw setting says it is still rich at idle because you have been keeping it close to 1 turn. (not a needle problem at all?) The float level could be high. Pilot air jet clogged. Lots to consider...
Check that the accelerator pump starts to squirt at 1/8(or a little higher) throttle. Just after the slide lifts up out of the way.
Plug readings are difficult unless you are sure of the throttle position giving the reading.
[This message has been edited by James Dean (edited 11-04-2000).]