So I installed the premium tuners kit from CV performance and everything seems to be going great except for two things. The acceleration right from start (0mph to 15mph) feels soooooo sluggish, and the bike wants to stall. The throttle response is amazing though and so precise but once I let out that clutch, my bike really wants to stall. Almost as if I was lugging the motor really bad. Secondly during mid rpm, I sometimes I experience these " slide farts" not the typical carb fart. I can hear the diaphragm of the slide as if it poping or farting. I lose alot of power when this happens... Everything else is amazing. The throttle response is insane, mid range to high range power (45,180) it pulls like crazy. After installing this kit, 2nd gear feels like 3rd, 3rd like 4th, 4th like 5th, etc. what I mean by that is I'll be 60 mph with ease in 4th when I use to be going 45mph with ease in 4th before the kit. Its awesome. The kit included a new diaphragm pump, jets (45,180 in now), emission tube, mixture screw, slide spring, needle and I bought a new slide from the dealership and the kit has more stuff but the other stuff wouldn't affect my performance. So has anyone else experience these diaphragm farts? And this extreme sluggish feel? Anyone know the solution to these problems?

 

I just got done doing the same thing as you, but I am not experiencing the same problems, just a thought but did you get both diaphragms seated right? and all the vac lines connected (pinched mine and got no gas flow)

 

I'd check that vacuum diaphragm on your slide. Put your finger inside the carb opening (engine off, of course) and see if it slides up and down without binding. You did mention buying a new slide, correct? What was wrong with the other one?

I'd also check to see if your accelerator pump/diaphragm is functioning as well, since you replaced it as well. Isn't there a small "o" ring involved in replacing it? I haven't touched my carb in 20 years, and was thinking of replacing my accelerator pump diaphragm at least, but she runs fine so don't fix if not broke, right?

A low end bog could be a lack of flow from accelerator pump, then your needle jet starts to provide some fuel as you go off the low end. My VW carb acted similar, and the accelerator pump tube was clogged up.

Just be happy it's a one barrel carb, you should try getting a Holley 4 barrel double pumper sorted out.

John

 

Yes I got both diaphragms seated correctly and vac line, theres more than one? The one I am talking about is the one in the back (center of the bike) . I just took off the carb again for the forth time lol and cleaned the hell out of it and made sure everything was perfect. Put sealant around the connection of carb and manifold. Lubricated everything. So I will see tomorrow how everything goes

 

Yes I bought a new one because CV performance recommends a new slide if someone has drilled a vacuum port hole greater than 1/8. The vacuum port hole was like 1/6 haha. CV performance (aka Ken- the owner) says holes that size and greater can cause sputtering. And when I took it out for a test ride, I hear the diaphram fart and associated it with the large port hole, but after replacing the slide, it didnt change. I am not sure if we have the same type of carbs but if we do than no and yes. there is no o-ring necessary to replace when changing the pump diaphram. there are two o rings seat on the acclerator pump right next to the diaphram that you could replace if you wanted to. One of mine actually looked worn out, good thing its easy to access the acclerator pump. You can also replace the spring which comes in the kit.I think the way to test its function is to just see if it squirts gas from the protruding needle in the carb and mine defintely does. Yea, I was amazed at how simipliest this carb is. Kind of reminds me of building legos not long ago lol. But unfortunately I didn't solve the problem yet, hopefully forth try is the charm

 

What type of exhaust are you running they look like drag pipes so do they have removable baffles ?
if so you may try opening your pipes up & see if that helps they may be restricting things.

 

Yes, we probably have the same carburetor, I think they've been the same since the accelerator pump was added. Where did you purchase the new slide?

Did you check to see if the slide moves easily up and down with your finger?

Did you blow out the ports and passages with air? Possibly something is clogging one of the ports. How did you clean your carburetor?

John

 

I did everything you mentioned and more, everything moves, slides, fits perfectly... it just doesnt make sense, it has to be something I am over looking and not taking to account of.... next weekend, I am gunna do the same thing and see if the vacuum line running to the bike is clogged, i dont know why it would be but I am out of options. See if the fuel line is clogged, again dont know why it would be but w/e, I am gunna do everything I can possibly think of

 

Where did you get the new slide?

Did the vacuum diaphragm come with?

I put the Dynojet kit in mine about 21 years ago, but I forgot completely what was up in the vacuum chamber. It must have been easy, cause I never had a problem, just forgot what all was up there. Haven't had to touch it since then, except fine tune the idle mix.

John

 

Woops sorry forgot about your questions

I got the slide from the dealership

Yes it did, theres no cracks or anything, it fit perfectly into the grove

I seriously do not think its the kit anymore, seriously has to be something else