have i got a bung bing

[malcom]

Hi I'm not sure where the problem lies, I'm assuming fuel. On todays ride while passing cars at around 5k revs it just would'nt rev any further, running rough, until I backed off a little, when it smoothed again.

Bike r80 with sibenbrock 1000 kit.

I dont know if it was one side only, or both, I realise there's not a lot of info to go on.

It was perfect up to 5000, any suggestions welcome, I'm not familiar with working on bings most of my bm ownership involved dellortos.
Cheers
Mal.com

[Kurt in S.A.]

Valve clearances? Torn carb diaphragms? Clogged air filter?

Kurt in S.A.

[ME 109]

Low float bowl level will give those symptoms. It doesn't need to be off by much, just enough for the sustained open throttle to overwhelm the fuel supply.

[Bill Smith]

Pretty close to textbook description of a torn diaphragm. The needle won't lift any further thus no more fuel pulled into the venturi.

Other question: how long has the Siebenrock kit been on? I had to go richer on pilots, mains and needles to feed the larger motor.

[Bill Smith]

Pretty close to textbook description of a torn diaphragm. The needle won't lift any further thus no more fuel pulled into the venturi.

[SteveD]

First thought was diaphragm. Sounds exactly like when it happened to mine years back.
Didja get to the M/GP Mal?

[dwerbil]

Had the same symptoms on my /7 during a weekend road trip. Read earlier of a roadside fix for a torn diaphragm is to remove it then stretch the tear a bit and add a drop of super glue to it to seal it. That little fix got me back on the road the remaining 400 miles like it was new. I replaced both diaphragms when I got back home.

[malcom]

Thanks everyone for that, I was thinking along those lines, I'll do the complete job on the carbies,

First thought was diaphragm. Sounds exactly like when it happened to mine years back.
Didja get to the M/GP Mal?

No Steve I bailed out, I'm glad I was!'nt there for the Sat deluge. We will try for the classic bikes in Jan.

Cheers
Mal

[daz]

Hi I'm not sure where the problem lies, I'm assuming fuel. On todays ride while passing cars at around 5k revs it just would'nt rev any further, running rough, until I backed off a little, when it smoothed again.

Bike r80 with sibenbrock 1000 kit.

I dont know if it was one side only, or both, I realise there's not a lot of info to go on.

It was perfect up to 5000, any suggestions welcome, I'm not familiar with working on bings most of my bm ownership involved dellortos.
Cheers
Mal.com

In case anyone else needed to know:
Tomakin is a small seaside village on the south coast of New South Wales between the major towns of Batemans Bay and Moruya. It is more closely flanked by the other small villages of Guerilla Bay and Mossy Point.

[grant81rs]

Thanks everyone for that, I was thinking along those lines, I'll do the complete job on the carbies,

First thought was diaphragm. Sounds exactly like when it happened to mine years back.
Didja get to the M/GP Mal?

No Steve I bailed out, I'm glad I was!'nt there for the Sat deluge. We will try for the classic bikes in Jan.

Cheers
Mal

The classic bikes in Jan is a great event, hopefully i will get there on the 78RS and its fresh gold markings.. Hopefully