'80 KZ 440 vacuum piston diaphragm repair?

I used the inner tube patch kit method on a Honda cb360 with very similar carbs. Unfortunately, the glue that comes with 'em doesn't seem to be gas proof. The patch would come loose after a few rides. I'd try some of that tougher glue guys are talkin' 'bout. I ended up selling the bike so I don't know the end result.

bountyhunter wrote:

Somebody on ebay was selling new rubbers for the 400/440 bikes a while back for cheap price (like $40)

I patched slits in mine with that urethane glue. Lasted a while.

That would be motoallparts. Unfortunately, he has raised the opening price to $49.99 & the bidding is more competitive this time of year... a set sold for $123+ this week. ouch. It might be cheaper to wait until winter... fewer bidders & maybe a lower starting price.

JMKZHI wrote:

bountyhunter wrote:

Somebody on ebay was selling new rubbers for the 400/440 bikes a while back for cheap price (like $40)

I patched slits in mine with that urethane glue. Lasted a while.

That would be motoallparts. Unfortunately, he has raised the opening price to $49.99 & the bidding is more competitive this time of year... a set sold for $123+ this week. ouch. It might be cheaper to wait until winter... fewer bidders & maybe a lower starting price.

That is ridiculous. I bought a good used set of pistons and needles from a dismantler for about $80 that had perfect diaphragms. Here is a place that makes new diaphragms and lists the ones for a 440 twin at 31 Pounds ( UK money) which is about $50 these days (?):

www.nrp-carbs.co.uk/kawasaki_carburettor_diaphragms.htm

I've talked to these guys, they seem pretty nice but the 440 slides have to be shipped to them so they can install the rubbers. Same with 750 twins, which is why I elected to buy used slides with good rubbers instead.

I just found the same problem with my KZ440 today after finally finishing with my rebuild. Fortunately I have a parts pike with a spare set of carbs.

I do not know if both the diaphragms are good, but if they are, and since I only need the one, I would be willing to part with it.

I also would like to add the rubber cement that comes in the tire patch kits will dissolve in gasoline and probably gum up your carburetor even worse, but I do wish you luck with it.

I haven't run the bike with that patch job, and it sounds like it was good that I didn't. I sent you a PM ZER. I'd love to buy yours.

Luckily (?) it's been raining like crazy here in Portland and I got sick for the better part of a week.

During my haze I decided that I HAD to put a front disc brake on this thing. The drum looks cool, but that's about all it does. I bought a LTD wheel off ebay for $50. I'm thinking I'll get it powdercoated. It will be nice to have a brake that works!

You ever get it running after getting the diaphragm?
I would like to hear that it worked.