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Hi, i have just noticed that the right hand side cylinder on my 1990 R80 Rt produces significantly less exhaust pressure than the left hand side when holding your hand next to the exhaust outlet. In addition the right hand side is considerably cooler.

I have checked the plugs and they are sparking well so am i likely to have poorly seating valves or something along those lines? As yet i have not had a compression test done.

Neither cylinder smokes and the carbs seem to be operating in synch.

Thoughts and advice would be welcome. Cheers Darryl

You didn't tell us at what rpm you find this symptom. If it is idle, then it is interesting, but not so important if the engine is in good working condition. Check compression. Small adjustments in the carbs will make quite a change in sound and pressure.

Do you do your own tuning?

Duane Ausherman wrote:You didn't tell us at what rpm you find this symptom. If it is idle, then it is interesting, but not so important if the engine is in good working condition. Check compression. Small adjustments in the carbs will make quite a change in sound and pressure.

Do you do your own tuning?

Hi, sorry i should have said that it is very evident at idle but still exists if you rev it. The engine sounds sweet with no unusual noises.

My Guzzi V twin gives even exhaust pulses on both sides.

Pretty confident that something is amiss so i have ordered a compression tester which i should have in a day or so.

Yes i do my own maintenance and have done so for years . Whatever it turns out to be it shouldn't be too hard to sort on a simple air cooled twin.

Darryl
Darryl

Read up on the type of tester that you get to be sure that your measurement is valid. For the old type in the spark plug hole, I have some info on my website that may be useful.

Minor adjustments at idle can make a huge difference in what you hear. This is very important when tuning by ear, which is still the fastest and most accurate for your bike. Few do it often enough to get good at it.

re: carb balancing,

Duane Ausherman wrote:...This is very important when tuning by ear, which is still the fastest and most accurate for your bike.

Few do it often enough to get good at it.

(My emphasis).
Bravo to those few who will "get good at it"
but perhaps the best rationale (for the many) to forsake pursuit of this archaic practice
and augment the old ears with the use of a manometer, vacuum gauges, or an O2 analyzer.

( I am not in the habit of wearing ear plugs when using a manometer )

SORTED!!!!!

A piece of rusty metal had come off inside the right hand silencer and was partially blocking the exhaust flow.

I had a feeling that this may have possibly been the cause so swapped the silencers over and the fault moved to the other side.

Removed the loose bit of metal and reinstalled silencers correctly and bike now running evenly with equal exhaust pressure pulses.

Looks like i need two new silencers now

Cheers Darryl

Hey, congratulations, doesn't it feel good to find that it was so simple and is fixed?
I wish more people would offer up what they find as it helps us all.

Of course you didn't give us any clue that would lead in that direction. Oh wll, we tried.

Thanks Duane for your help.
I had no idea that the silencer was going to be the culprit but seeing as my compression tester had not arrived I stumbled on it being a long shot possibility over a cup of coffee this morning .
Seeing as it was such a quick option to remove the two silencers i gave it a go. RESULT!
I learnt a long time ago that it's crazy to rule anything out of the equation until you have checked it.
I will still check compression when the tester arrives following procedure info on your site.

Thanks again.

Kind Regards Darryl

Darryl Flynn wrote:SORTED!!!!!

A piece of rusty metal had come off inside the right hand silencer and was partially blocking the exhaust flow.

I had a feeling that this may have possibly been the cause so swapped the silencers over and the fault moved to the other side.

Removed the loose bit of metal and reinstalled silencers correctly and bike now running evenly with equal exhaust pressure pulses.

Looks like i need two new silencers now

Cheers Darryl

I have a set of mac whisper tones used but in good condition I'll sell ya, cheap.

I would have been very interested but postage to England would probably be crazy.

Darryl