freemoRR
Garage Warrior
very true. No sense twisting screws until I know what I'm adjusting. I have a few spare moments now. stay tuned.
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praying to the carb gods for alittle advice!
- Thread starter freemoRR
- Start date
freemoRR
Garage Warrior
so its 180 main, PF9 needle pos#3, 25 pilot, air jet removed, and the needle jet is P-6....guess its time to play with clip positions?? any other tricks in the dealers deck?
It looks like you have good baseline jetting in place--assuming that the vendor installed genuine Mikuni brass and not knockoff trash. There is no PF9 needle; that's 6F9, and that's what you want. Sad to say, there are no tricks. Unless you're working with a "rolling road" and EGA, it's all trial and error and observation of engine function. The Sudco Mikuni Tuning Manual has a very good list of functional tests for mixture imbalances (rich/lean conditions). I strongly recommend it to anyone who's trying to dial aftermarket carburetors.
freemoRR
Garage Warrior
ok well based on what I've read...the jetting I currently have is a semi-decent starting point, possibly on the rich side according to Grizld1...and the fact that the damn thing wont idle warm is actually leading me towards a rich condition...I think I'm letting the dry plugs and hard start throw me for a loop..I dont have the popping or idle hang but the engine seems to get pretty warm...you'd think if the bike was rich enough to flood out itd run a bit cooler..what would you suggest for a step down on the fuel side of things? as a starting point?....also, a good place to find jetting for the vm34s? website you'd recommend? thanks again for the help 5twins. New to these things, but I'm a quick study.
freemoRR
Garage Warrior
sorry griz your comment popped up as I was typing mine. 6f9 is what I have...my mistake. I will try and track down a copy, its not online by chance is it?
This outfit is highly rated: http://www.carbparts.com/mikuni.html
Manual links .....
http://www.mikuni.com/fs-carburetor.html
http://www.mikuni.com/pdf/vmmanual.pdf
This place has very good jet prices but I'm not sure if they're all genuine Mikuni jets. Some, like the mains, appear to be .....
http://www.sunlpartsonline.com/mikuni-carbs-jets-c-699.html
http://www.mikuni.com/fs-carburetor.html
http://www.mikuni.com/pdf/vmmanual.pdf
This place has very good jet prices but I'm not sure if they're all genuine Mikuni jets. Some, like the mains, appear to be .....
http://www.sunlpartsonline.com/mikuni-carbs-jets-c-699.html
FreemoRR, I can appreciate your hesitation to charge into the job blind, but nobody can tune those carbies for you at a distance; just be sure to make one change at a time, assume nothing, and don't be afraid to make mistakes; nothing you do will be irreversible. Re. tuning, follow the directions in the VM section of the XS650 Garage Carb Guide for adjusting the mixture screws and use engine behavior as your guide in fine adjustment. The Sudco Mikuni Tuning Manual is available from 650 Central and Mike's XS. Yeah, there are some online specs and illustrations available free, but those lack the detailed diagnostic procedures included in the Sudco manual. I've also written a carb manual for the Yamaha 650 Society which can be ordered from Don Lawson, the Society's Executive Director; 26 pages on OE and aftermarket carbs for $17. Google for the Society's URL, which will give you relevant addresses.
freemoRR
Garage Warrior
Perfect. Thank you gentlemen. I woke up today to pouring rain, but tomorrow may be nice enough to do perform alittle more trial and error. In the mean time I will order the manual and a range of brass I can play with. You can never have enough good reading. If I make any headway I will be sure to post it , so that it may help anyone else pinned down in the trench!
On the plus side, I got an email today from a guy who might want to trade me a sweeeeet 78 xs chopper for a custom "reaper" 600RR that I built 2 winters ago. If I make the deal ill be sure to post pics!
-FR
On the plus side, I got an email today from a guy who might want to trade me a sweeeeet 78 xs chopper for a custom "reaper" 600RR that I built 2 winters ago. If I make the deal ill be sure to post pics!
-FR
freemoRR
Garage Warrior
UPDATE: raised needles up one notch (lowered clip to position....4? I believe?). reset mix screws 1.5 out. synced slides with the drill bit and adjusted cables to get em in the ball park for opening sync. bike immediately started and idled, first kick. that has never happened yet!! and without having to give her the ole throttle roll either!! (also a first). shut off and kicked over multiple times, started right up every time. The slight burny lean smell at idle is now replaced with a nice fuely smelling mix. Its been raining all day so she wont see the road tonight, but I think I'm definitely in the right direction. I'll do a few hard laps tomorrow if weather permits and re-assess. either way, I'm feeling fairly optimistic right now!
