Popping on right cylinder

[Geckohunter]

New to me 1983 R65 been SORNed (off road with tax suspended) for a year, nice condition.
Q. 1. When I start it, it pops on the right exhaust, smoothes out somewhat at revs and lessens with warm up.
There is a petrol filter added between tank and left carb, is this wise as it restricts the fuel flow a tiny amount, would this make the furthest carb run lean?
Should I ride it longer to see if storage has caused some problem? Or, clean right carb needle. Or check for electrical fault, such as grounding wire?

Q. 2. How would I know if this bike has been converted to run on Unleaded fuel? The previous owner has gone quiet on me.
I am the new owner for just a few weeks and cannot ride it yet as I'm going through my full bike licence. So, after riding Honda CD175 in the 1970s, Honda CG125 and CZ175 in the 1980s then spending 20 years out of biking I made a nice choice of an R65 but have much to learn.

[Bob_Roller]

If nothing has been done to the bike since you've gotten it .

It may need just some cleaning/adjustments .

The fuel filter shouldn't cause an issue, unless it's got a lot of sediment/debris in it .

I would suggest removing the carburetor float bowls and check for water, sediment debris, etc....

A carburetor synchronization check, just to see if they are adjusted correctly .

Check the valve clearance adjustment .

These bikes act unusual when the valve clearance closes up .

Don't concern yourself about unleaded fuel, I know since the '81 model year bikes they were designed for unleaded fuel, I'm sure BMW didn't make bikes both ways .

[Geckohunter]

Thank you, very reassuring and quick suggestions and information. Carb float bowls will be checked for water/sediment.
Fuel filter inspected.
Carb synchronisation will be done when I get my bike to my home (it is stored in my dad's garage until I pass my test and can assert my rights to it  ). A biker mate here has a carb synchronisation kit.

I've read on this forum about valve clearance checking and will progress to that when I treat my tool box to some feeler gauges. Or borrow my dad's and impress him by going into that job with confidence gleaned from this forum.
Great news about not worrying about unleaded fuel, thanks (I wondered if unleaded was perhaps leaner fuel).
My instinct tells me valve clearences, but as you say I must first do the essential carb float bowl maintenance.

Ta.

If nothing has been done to the bike since you've gotten it .

It may need just some cleaning/adjustments .

The fuel filter shouldn't cause an issue, unless it's got a lot of sediment/debris in it .

I would suggest removing the carburetor float bowls and check for water, sediment debris, etc....

A carburetor synchronization check, just to see if they are adjusted correctly .

Check the valve clearance adjustment .

These bikes act unusual when the valve clearance closes up .

Don't concern yourself about unleaded fuel, I know since the '81 model year bikes they were designed for unleaded fuel, I'm sure BMW didn't make bikes both ways .

[Barry]

I wondered if unleaded was perhaps leaner fuel).
My instinct tells me valve clearences, but as you say I must first do the essential carb float bowl maintenance.

I think modern fuel is probably a little leaner than what was around when these bikes were built. Even with no other changes like unleaded the addition of ethanol alone will result in a slightly weaker mixture as it reduces the overall calorific value of the fuel.

Popping does sound like a weak mixture particularly as it lessens with warm up. A fraction turn out on the mixture screw on that that side should help. But before you do that I would go ahead and make sure everything else is good particularly the valve clearances which will impact on idle mixture settings. To add to what Bob has mentioned, while you have the float bowls off I would check float levels are the same both sides.

[tvrla]

Expect the settings to change as the bike accumulates some miles. The compression won't be the same in both cylinders most likely (from the hybernation) which will change as it gets ridden. Just make sure the basic settings are good to begin with, and after 500-1000 miles everything will normalize and stay pretty much the same from then on. But till then, expect to fiddle with it a bit.

Agreed on the unleaded gas - it really didn't have much of an effect on valves and there's not much you can do about it's lower quality. It just means you've got a bit less power. No biggie.  

[beemer]

I too have a in line fuel filter,if i don't use the bike for a while and it get's a bit empty i find that a simple few squeeses of the fuel pipe fills it up and i'm ready to go.