How to make a CNS carb stay on the intake tube?

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Ok heres one for you guys running a CNS carb. What did you have to do to keep your CNS carb onto your intake tube? I have a billet intake and my CNS just wont stay put. I have used a dremel tool to open the slot, can I just keep opening the slot? Should I use gas proof sealent to try to glue the carb in place? How did you guys get your CNS carb to stay in place? Thanks
 
Other than apparently you can mount the CNS w/the billet intake (I didn't think ya could lol), here's my previous posts;

BarelyAWake said:
I'd not cut the slot at all as there's a chance for a vacuum leak (it's pretty close already) and worse yet I've heard problems w/cracking if cut & compressed too much.

I simply roughed up the end of my intake manifold a bit to give the spacer something to grip and added a touch of 'Seal All' (fuel resistant glue): Amazon.com: Seal-All, 3/4 oz: Home Improvement to the outside of the spacer to grip to the carby... tho I've removed the carb a coupla times since then & haven't bothered w/regluing - I think it's all the roughed up intake that's working for me.

I've had absolutely no problems with carb movement or rotation - but I'm also not using the extended intake *shrug*
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BarelyAWake said:
It's just the nylon[?] spacer allowing the slip, cutting additional slots (or bigger) will just cause the spacer to compress - breaking the aluminum carb mount...
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I have the billet intake and tried everything possible including, hack saw blade width cut for extra clamping squeeze,silicone and ruffing with 180 grit. Fix was wrapping wire around the back of the carb to up and around the top portion of the engine cylinder and twisting wire tight. Not very noticeable at all but works excellent!, could only get about 1/2 mile before and have about 15 miles so far with no problems.
 
Nougat said:
In order to keep the carb on the intake, the inside diameter of the spacer needs to be close to he outside diameter of the intake, so that minimal clamping force holds it tight.

Adding a strip of foil between the carb and the spacer effectively makes the ID of the spacer a little smaller. Nthis reduces the amount of clamping force needed to make it tight.
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Not to argue...that makes more sense than what was posted on page 1 "Put it in between the carb and the plastic spacer"...
 
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I took the rubber gasket out of the carb and the o-ring on the billet intake disintegrated and came off. When I pushed the carb all the way onto the billet intake, the heat eventually caused the white spacer to fill in the groove where the o-ring was and to fill out the little space between the carb body and the bands where it screws tight.

This caused the carb to stay on tight and I almost have to completely remove the carb clamp screw & jimmy the carb back & forth in order to take it off. Holding and sealed good. I keep the split in the spacer toward the bottom...

See my post toward the end of the Love the CNS Carb thread for advice about the hoses and settings, if you have any troubles... I'm using the original needle from the old carb with the c-clip at the top of the needle, in order to have a better air/fuel ratio.
 
Same problem here, except I was running duel Boost Bottles, and got my motor so wrapped out that the vibration broke the manifold at the base. That was ok, I have a new Grube kit in back I can use the manifiold from it, except while trying to keep it tight, it broke too, right at the base.

I am going to use two peices of hose clamp, drilled out to mount on the intake bolts, and then, with both sides of the hose clamp peices, I can run zip ties around the carb. Wire around dosen't sound to bad either, cept ties are easier to carry is all.

How about replacing the teflon or whatever it is with something else?? Maybe rolled up inner tube?? Just a thought, and please let me know if you come up with something to fix this major problem.

Thanks,

Gary
 
Hiigel said:
Same problem here, except I was running duel Boost Bottles, and got my motor so wrapped out that the vibration broke the manifold at the base. That was ok, I have a new Grube kit in back I can use the manifiold from it, except while trying to keep it tight, it broke too, right at the base.

I am going to use two peices of hose clamp, drilled out to mount on the intake bolts, and then, with both sides of the hose clamp peices, I can run zip ties around the carb. Wire around dosen't sound to bad either, cept ties are easier to carry is all.

How about replacing the teflon or whatever it is with something else?? Maybe rolled up inner tube?? Just a thought, and please let me know if you come up with something to fix this major problem.

Thanks,

Gary
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Buy the new billet intake made for the CNS carb. You can get em from priate cycles.
 
After many calls to Mike at Spooky tooth, i came up with a decent solution to the lame CNS intake design. I removed the crap plastic white thing and replaced it with a strip of heavy duty rubber that is a touch thicker than the plastic it replaced. I also used a piece of cut rubber from a speargun band as a spacer that goes between the red plastic cover of the air filter and the down tube of the bike frame essentially sandwiching the carb onto the intake tube. Now it can't back off the tube.
 
Here is my solution.... so far... so good.

To make it cleaner looking i should probably cut the excess off... but I'm was lazy and just wanted to see if it would work... and so far it has.

I had to heat the (clear heavy duty with nylon) hose up in a glass of water i put in the microwave, then I finally was able to get it onto the intake.

Then I took the crappy plastic ring out and just opened the carb clamp up real good and slid it over. Nice tight fit. No movement at all.

DSC06342.JPG


I don't really need the silicone on the back anymore. But like I said. I was lazy. I may peel that off today.
 
Thanks for the idea and pics. The only issue I have had since using the rubber is that it moved out a bit. It seems to have stopped and performance is acceptable so I am not messing with it unless it gets worse. I may try the tubing next time. Do you think that slit in the top of the carb should be sealed? What did you use to seal it?
 
So far the heavy duty plastic hose is working much better than the rubber I had tried before and abandoned immediately after I saw how much play the rubber had. The slip on my carb did not need any seal... in fact I ripped it off to recheck. It seems to be working well. It's just metal to washer. I have a large intake on order from Pirate. I just thought I would give this a go until it arrives. Think I'll keep it on and see how long it lasts before using the large intake. You know... test for the good of all.
 
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