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Posted: Tue Nov 24, 2009 4:04 pm
Does anyone know of literature regarding the CVK32 carbs, or would anyone be willing to give me a breakdown of the functions of the carb. I mean, I'm not a total idiot when it comes to carbs...but I would like to know more.
Other then gaining knowledge, I do need to solve why my left carb is popping when I slow down. I have the idle screws matched as far as I can see, and the idle mix set to standard 1.5 turns, I've tried more/less turns on the mix screw and that doesn't help. The compliance fittings seem to be in good shape as well.
So if any ural-pro's would like to share some insight it'd be greatly appreciated.
Posted: Tue Nov 24, 2009 4:24 pm
get a twinmax, the screws settings you read about only get you close, a twinmax will synk the carbs and get you dead on.
here is the carb breakdown/info you requested
Posted: Tue Nov 24, 2009 4:58 pm
Yeah I've thought about getting the twinmax, maybe when I get some spare money.
I went through the carb dis-assembly on the site a few months ago so they should be in good shape.
Posted: Tue Nov 24, 2009 5:05 pm
Everyone has a different opinion on this, but my CVK32 carbs drove me nuts in 2002 and I bought 2 K-68 carbs and have never looked back. This year I replaced the old k-68's carbs with 2 new k-68's.
I still use a twinmax to dial them in.
NO MORE LEAKING COMPLIANCE FITTINGS!!
Posted: Tue Nov 24, 2009 7:46 pm
Here is an excellent link that will tell you almost everything you need to know about the carb, albeit a 40MM.
If you don't have a lot of money to play with jetting, I would get yourself 1 to 4, 2mm stainless washers and insert them (max two each side) under the needle jet on your carb. This mod made a huge improvement with popping on decelerating on my bike, even before I made my airbox mod. Just remember, when you take the diaphragm out, let it sit for a while to air out, as it can be hard to re-install while saturated with gas.
Do a search on needle shim and see what you find.
Posted: Wed Nov 25, 2009 6:22 am
Posted: Wed Nov 25, 2009 11:57 am
Here's a manual and exploded view diagram I found on the CVK carbs.
Posted: Wed Nov 25, 2009 11:59 am
Sometimes the "popping" on decceleration can be casued by other things such an exhaust leak.
Posted: Wed Nov 25, 2009 12:47 pm
Agree with Johnny...if all is in order with the carbs...then (1) look at the "J" pipes coming off the head. On the 2002 engine, they are a press fit, if they are loose and sucking air on deceleration...you'll get a pop, pop. (2) Check the union nut at the J-pipe/muffler junction, if loose you'll get the same.
Loosen hanger clamp on J-pipe (need to remove cylinder bar on left side) and tap pipe in with a hammer/mallet at the apex of the 90 bend to seat. If you so desire you may, remove pipe and slather each end with red RTV sealant (both pipe/cylinder boss and muffler) and then tap the pipe in.
Just grab the J-pipe when cold and see if you can move/rattle it. If so, do the above. If not, you don't have the carbs set up correctly or have a problem in the innards of the offending carb.
The idle mixture screw (forward and underneath the carb.) only affects the first 1/4 of throttle...so if you are coming off throttle when popping occurs...you problem is not with the idle circuit.
Last, never trust the advice given by a guy wearing latex gloves in a maintenance video.
Posted: Wed Nov 25, 2009 1:58 pm
Also check your valve tappet clearances. An overly tight exahust valve may exhibit the same symptom.
Posted: Wed Nov 25, 2009 10:25 pm
Wow, thanks for all the input! I have quite a bit of reading and tinkering to do now.
Posted: Sat Nov 28, 2009 4:50 pm
I made one like this but put motor oil in it. My thinking being that if things got a bit out of hand I would rather have oil sucked into engine than water.
The advice I got suggested using a yard stick and filling tubing with oil to about the 27 inch level.
Posted: Sat Dec 05, 2009 8:53 pm
Built That Manometer last weekend but used Marvel Mystery Oil as the fluid. Finally got a chance to use it today after riding home from work.
Now I thought I had the carbs fairly well set until I started it up,damnear sucked the oil into the rt. carb.
Got it all balanced nice.
Note: both idle screw and cable adjustments are VERY sensitive so only go a tiny bit at a time.
It is much smoother now and will do a cold start check tomorrow.
I still need to re-jet so this was just practice!
Posted: Sat Dec 05, 2009 10:43 pm
Re-jetting does not require resync'ing.
Posted: Sat Dec 05, 2009 10:59 pm
BillyG wrote:Re-jetting does not require resync'ing.
Yea, I know,but just got to go thru the steps.
I'm That nutty....