Living in denial failed - again.

[Rikugun]

Last season I noticed grunge beginning to accumulate on the rear carb. My guess was fuel was leaking from somewhere and I didn't really want to deal with it so I ignored it.

Fast forward to the first start of this season and fuel is puking from that carb. It seems to be coming from around the accell pump housing so I removed the carbs and separated them to gain access. One of the 4 screws holding the cover on was a little loose so I hoped that was it. I pulled the cover and didn't see any holes in the diaphragm so reassembled and filled the carbs to do a bench test. Fuel is leaking from within the cover whenever the throttle is opened. Clearly the diaphragm has failed where the metal center and rubber are joined.

The carb parts were installed very late in the 2011 season and lasted 3 full riding seasons although I'm not exactly sure when the leak started. I'm not sure if the Keyster parts are questionable, mine was from a bad batch, or maybe my adjustment was too severe and the diaphragm was stressed more than need be.

[turbosteve84]

Did the Keyster parts include the diaphragm? Do you still have the original part? I have no experience with this part on the Vision, but on other bikes if the diaphragm has no tears or holes it's usually good to go. --Steve

[Rikugun]

Yes, and although only one is required per carb set, both kits come with one. I've since installed my "spare" and the leak stopped. I was hoping not to have to use that diaphragm so soon.

I probably do have both originals from my 2 sets of carbs but they are quite inflexible and therefore poor performers. I don't recall them leaking when they were removed from service.  To my knowledge this one is the first to leak like this.

[jefferson]

Try to find some ethanol free fuel. Your rubber parts will love you for it.

[Rikugun]

I've looked and it's not practical where I live. Actually I'm growing tired of the "corn squeezins" excuse. Ethanol blends have been around long enough for engine and parts manufacturers to make the adjustment. I'm not even sure if that's to blame which is why I didn't mention it initially.

[Old Man Zzzz]

Adjustments are being made, but remember your dealing with a year model, that adjustments weren't
being considered, and since its a discontinued model, there you go.

[Rikugun]

Keep in mind the part in question is not NOS but rather aftermarket of current production.