2002 1150 rough at low revs

[John Leah]

HI,

I've had my 2002 1150GS for a few weeks now, put three tanks of fuel through it and had a couple of longish, spirited runs but am still not happy when pulling away. It stalls all too readily, the engine 'fluffs' when opening the throttle at low engine speeds and 'hunts' at higher revs.

Even though it's seven years old it's still only done 13,000 miles (genuine) and is in excellent condition so I initially put the engine hesitancy down to lack of use (400 miles between the last two MOTs) so expected things to improve as I racked up the miles. But it hasn't.

It has the standard exhaust but I have a Remus can and 'Y' piece to fit when I can find the time. Tickover is correct.

So, any thoughts on what it could be?

Cheers
John

 

[jimbogs1200]

When was it last serviced?

 

[Canuck]

Steptoe would be the better one, but how about checking the valves, end rockers or throttle cables... that's where I would start.. with afew basic tools you could do these things all yourself ... instructions on 'how to' is easy enough to find , just use the search function!


all the best!

 

[John Leah]

It has a good service history and last saw a main dealer about three thousand miles ago and has a few miles to go before the next scheduled one. The problem could be that service was nearly four years ago!

I'm off to Scotland on it in a few weeks time (from Devon) and planned a dealer service prior to that just for peace of mine but wanted to put a bit of fuel through it first.

 

[Canuck]

John, send me an email at [email protected] and i'd be happy to adjust your valves and end rocker for you to see if that does the trick.. I'm only a few miles away! Give me a shout and we'll take it from there...

 

[Colban]

Is it a twin or single spark motor?.
Have you tried the Cat Code Plug (do search) to try and compensate for the exhaust mods.
Also check the TPS voltage along with valves/end float/Throttle body balance.
Maybe try different spark plugs

 

[Steptoe]

Is it a twin or single spark motor?.

This is a very important question concerning rough running. Let us know which engine you have before trying anything.

 

[John Leah]

Colban came up with some good ideas:

> Is it a twin or single spark motor?.

I had to go and look! All I can see is a single, central plug in each cylinder. TBH I hadn't even realised that they came with a twin plug set-up. I've had an airhead for nearly thirty years and twin-plugging them was a popular conversion to improve combustion so is twin-plugging an oilhead an aftermarket solution for the same 'problem' or something as provided by BMW from the factory?

> Have you tried the Cat Code Plug (do search) to try and compensate for
> the exhaust mods.

I still have the standard exhaust - the Remus I mentioned has yet to be fitted.

> Also check the TPS voltage...

I had to read up on this and can see the similarity in symptoms so it's something to check.

> ... along with valves/end float/Throttle body balance.

Canuck lives nearby and volunteered some workshop time which I'm eager to take him up on. I have a little mechanical experience but there really is no substitute for looking over the shoulder of someone who's already done the job in hand.

> Maybe try different spark plugs
Different grade or just new ones? I haven't even removed them to check on condition. Perhaps I should have...

Cheers,