Replacement hose clamps?

[mrhedges]

Got my carbs rebuilt by Chef1366. Finally got it back together and got the bike running. It will start but will run up to 3K then down to 1k. Throttle does nothing. I assume I have a vacuum leak. The Airbox boots are brand new (replaced them myself and seated them correctly) The Carb boots aren't brand new by seem fairly pliable. I took one off and checked the O-ring and it seems round and not rock solid. I took the air-box cover off and realized I cut the new seal a tad to short . So I guess its back to Lowes Should I replace the hose clamps too? It seems like new ones would be easier to get on and off.

[steve murdoch]

Best to get oem boot clamps.
They are the proper width for fitting in the boot grooves and won't cut the rubber.

[Burque73]

Beware, those carb boots can be pliable and "look" good but still separate from the metal base enough for air to get in. Also the boot O-rings are rock hard if still original. You can spray some carb cleaner around them to find air leaks. When the idle shoots up, you found the leak.

[Burque73]

Just reread your post, hopefully all four o-rings are like the one you checked.

[mrhedges]

Is there a way to check for this?

[bwringer]

Once you've removed the o-rings, replace them (use OEM or Viton o-rings only -- standard buna-n o-rings fail quickly because of the heat). O-rings are cheap. And yes, the OEM clamps are the only way to go. New ones are also pretty cheap.

One common issue is that the intake boots still seem to look and feel OK, but the rubber shrinks over the years and the clamps won't seal. So I'd replace these while you're at it. Eat baloney sandwiches for lunch for a week or two if you have to -- it's well worth the expense, and you'll be set for the next 20 years or so.

Another VERY common issue is that the inner two airbox/carb boots fold up or slip off. It's really hard to see or feel what's going on, but this happens quite often. Get a mirror in there and make sure you check them all the way around.


You can check for intake leaks by spraying WD-40 around the boots and seeing if it gets sucked in and makes smoke. However, this really isn't very effective for small air leaks that can still make the bike run like poo.

[Burque73]

Is there a way to check for this?

To check if the rubber is separating? With the boot removed squeeze it to see if a gap opens at the base. Newer ones will be very well bonded together.

I've read here that Wd 40 works to spray around them while the engine is running to find leaks too. I used carb cleaner but that's powerful solvent. Looking at your intake boots in another thread if that's what caused the melted rubber, I'm going to reconsider using carb cleaner.

Those O-rings might be compressed enough to not be usable again if you remove the boots. They're cheap enough to just order new ones, better safe than sorry.

When you said the throttle does nothing, was the engine still cold? Idle shooting up could be just a simple adjustment on the idle control knob . Chef did my carbs too and that's all I had to do out of the box, just dial down the idle and they were good. I should have vacuum synched to my bike right away but now I know.

Edit: I guess I type too slow, haha. Bwringer's reference to wd40 confirms what I'd read earlier.

[mrhedges]

You guys have been really helpful. It's good to know those clamps are really specific to the bike. I just ordered new O-rings from Robert (better safe then sorry) while I was at it I ordered replacement hardware for the carb boots. I am gonna take them off an check. Probably won't have time until tuesday or maybe sunday. Thanks!