Got an odd one here good people I did search but cant find anything that matches my issue. This is my first T3, it had been stood unused for a long time before having only done 15500K, and the guy I brought it off recently recommissioned her, the carbs have been ultrasonically cleaned and all fluids and some pipework replaced, however it will not rev out in top, stops about 20 mph of its max like its hit a wall. Revs to the red line in lower gears but not the higher gears (5th or 6th) seems like a fuel issue! One think that is odd is that I was out yesterday on its first decent run, which is where the issue was noticed, stopped off for a burger and when I restarted, pulled on the choke but forgot to turn it off all the way home and the symptoms were the same, I only noticed the choke was on when it idled at a roundabout at 3K. when almost home. As I said its been cleaned out, filter and all and seems to run fine through the range, its just the top end so any ideas or things to check would be great thanks. Since then I have changed the filter for a Pipercross element, jetted to 137.5-135-137.5 main and 42 pilot, standard needle position, carbs inspected again, fuel filters clean, tank vents clean. Doing my head in now. HEEEEEEEEEEEEEELP
lol. just sayin, so it goes to within 20 mph of top speed, well thats approx 110 mph or so,mmmmmm. you say it revs ok in all gears except top 2 so i wouldnt think it was fuel or it would be the same in all gears surely. not sure about the pipercross filter and jetting, would guess main jets aint right,maybe blocked as it runs good lower down. guess you tried running it with the tank cap open to see if there is a vacuum last guess but a bigger job, valves? but if it starts ok and runs ok probably not that
Take it for a run minus the air filter. It may be over oiled. This will tell you one way or the other.
Not run with the tank open but have opened up the vent hole sizes and checked vent pipes but worth a go Dave
Exactly. I am suggesting in a roundabout way that you eliminate possibilities. If it is not 'muzzled' and the ignition checks out you have either got a fuelling issue or maybe poor compression. How is oil consumption? You might need a rolling road re-tune.
It's only done 16K but was sat for 10 years before a refresh Carbs ultrasonically cleaned and jets are new
To be honest, it could be a number of things from clogged petcock on the fuel inlet side to an exhaust a bit furred up with corrosion (unlikely!). For a vehicle that has sat I can only suggest you systematically work through fuel supply, air supply and exhaust. I cleaned my own carbs ultrasonically but tank rust particles in the mesh petcock filter were part of the problem, as was the inline filter and a slight kink in the fuel hose that limited flow at full chat.
This is getting confusing as there are two threads with the same name both by the same person asking the same question ........ This one under Tech Help And one under Sprint & Trophy Amalgamating the two would probably yield less confusing answers and save people doubling up on suggestions
Silly question - have you checked the throttle ' throw ' by that I mean when on full throttle does the carb move fully open?
Going back to my reply earlier, stupid advice from me, dont try riding with tank open, that is for static test only, I realised after. sorry
I remember seeing a fella gazing into his fuel tank - with a cigarette in his mouth - I moved away quick like
Be honest now ......... why do bikers always stop at a petrol station to light up and smoke, often whilst topping up the tank ???
