Hello
I have a small problem that is driving me crazy. My engine will not run smoothly at 2000 rpm. It seems to be 'hunting' that is running faster then slower. When I run it up to 3,000+ revs everything smooths out. As I normally run the engine at 2,000 revs around town and in traffic this is very annoying.

I have stripped and cleaned the carbs. They were very dirty but now spotless. I have balanced the carbs. The pilot adjuster screw had been turned out two full turns on both carbs. The carb rubber manifolds have been checked and all vacuum hoses have been replaced.

Also at tick-over it doe not run smooth. If I rev the engine it occasionally pops on deceleration.

Does anyone know why this engine will not run smoothy at lower revs?

Note: my TR1 has XV1100 barrels and pistons. The heads are TR1. The camshafts are original TR1. The carbs are all jetted as TR1.

Thank you.

Kevin
Salisbury, UK.

I turned the mix screws out two full turns. The tick over is nice and smooth but it is still hunting at 40 mph/2,300 revs. Above 3,000 revs everything smooths out.

I have replaced all the needles and jets, the diaphragms are good and the carbs are spotless.

I agree with you that the slow running jets need to be a size larger.

Has anyone on the forum increased engine size to 1100 and had to increase jet size? If so, what should they be increased to?

Thanks for the support.
Kevin

Thanks Greg

Where did you get the increased size main jets from?

Thanks Greg

I get my Keyster kits from NRP Carbs in the UK. I will try them first.

Thanks again for the help.

Are you going to the rally this year? If so, for your help, I would like to buy you a beer.

Kevin

Hello Greg

I did mean the TR1 rally in Germany this year.

But, I would like to go to the event in Pendine. I have visited Babs a few times and would like to see bikes race on the sands. When is it on?

I contacted nrp (nrp-carbs.co.uk) they do stock over sized jets. They advised that I go one size larger on both pilot and mains. I will follow their advice, so I am going to 45 on pilots and 128/130 on mains. Available jets and costs are below.

NRP stock pilot jets #45 at £4 + vat (47 is available by special order from Japan)
Main jets #128/130/132/134 at £4 + vat each

Regards
Kevin