Hi

I have just put a 1989 XJ600 back on the road after it has been standing for a number of years, I have got it running ok and it accelerates fine up to about 50 to 60 MPH and then it seems reluctant to go any faster does anyone out there recognise the symptoms if so any help would be gratfully accepted

Thanks Gary

Hi

I have just put a 1989 XJ600 back on the road after it has been standing for a number of years, I have got it running ok and it accelerates fine up to about 50 to 60 MPH and then it seems reluctant to go any faster does anyone out there recognise the symptoms if so any help would be gratfully accepted

Thanks Gary

Check the fuel filter and if it has a breather pipe on the tank, check it isnt trapped or kinked

Check the fuel filter and if it has a breather pipe on the tank, check it isnt trapped or kinked

That modal didn't have an inline fuel filter (only the gauze in the tank) nor breather pipe ( as such just a tube from the venting filler cap that ran to the back of the tank.) the rubber tube may be blocked but with a venting fuel cap I guess that would not make that much difference (unless the cap vent is blocked). Perhaps we need to know on the engines state of health is the compression ok, engines left for years in one position can end up with valve seats that are rusted (lack of compression on the affected cylinders). Do we know wether the bike pulls well to 55 then stops going or is it a struggle to get the bike to that speed. Has the motor had a setup service (carb clean, wire check and compression test) until that is known it's difficult to work out ... my gut feeling is with the carbs, when M/C sales slumped in the early/middle 80's there were quit a few XJ550's (same motor just smaller bores) that were left in their crates to long and ended up with the symtoms suplied we need more input from Gaz as to the state of play with the bike

Regards Jim

That modal didn't have an inline fuel filter

I didnt say it did, but the gauze in the tank is a 'filter' and on a bike thats nigh on twenty years old and also been standing and showing these symptoms, its where i'd go first

Do we know wether the bike pulls well to 55 then stops going or is it a struggle to get the bike to that speed.

Yes as gaz said, it accelerates fine to 50 - 60

Thanks for all that but the carbs have been off, cleaned and re balanced it does accelerate fine up to about 50 and then moves up slowly to approx 60 and then will not go any faster it feels like it wants to but seems to cut in and out if I slow down it will again ride fine up to 50 acceleration is good I was wondering if it could be something like the coil breaking down under load? but I know a lot more about car engines than I do bikes. Compression test all seems in order.

Gary

Yes could be the coils breaking down, could also be the pickup coils breaking down for the electronic ignition, But as i say make sure you have a good unrestricted fuel supply

It wants a retirement plan

Thanks for all that but the carbs have been off, cleaned and re balanced it does accelerate fine up to about 50 and then moves up slowly to approx 60 and then will not go any faster it feels like it wants to but seems to cut in and out if I slow down it will again ride fine up to 50 acceleration is good I was wondering if it could be something like the coil breaking down under load? but I know a lot more about car engines than I do bikes. Compression test all seems in order.

Gary

perhaps its restricted?

Have you tried new plugs & caps ?

Thanks for all that but the carbs have been off, cleaned and re balanced it does accelerate fine up to about 50 and then moves up slowly to approx 60 and then will not go any faster it feels like it wants to but seems to cut in and out if I slow down it will again ride fine up to 50 acceleration is good I was wondering if it could be something like the coil breaking down under load? but I know a lot more about car engines than I do bikes. Compression test all seems in order.

Gary

They are pretty much the same as far as diagnosing the route cause of problems, the soloutions may be different due to part variations and layout. If you have reasonable mechanical knowledge and your gut is saying coils, have a look.