250 running issues

[norman]

Hi Folks,
Recently bought an `81 250 off of ebay and I am having problems getting it to run right. After a good service, I have the bike starting and ticking over okay but when you take it out for a run it struggles to pull away and struggles to reach 50.
So far I have de-coked the exhaust baffles, cleaned and set the carbs and changed the plugs, air filter and gearbox oil. All were badly needing attention.
Do you think I should be looking to de-coke the top end or should I be sticking with the carbs?
I also have a slight problem with clutch slip but I haven`t looked into that yet.
Any advice welcome,
Norman

[Tone]

Are the carb slides in the right carbs as they are different? The large cutaway at the bottom of the slide should face back towards the airbox. Tone.

[K.B]

Sounds like crank shaft oil seals are leaking !

[Norbo]

Both Tons an K.B have good points worth a look at . If it wont pull past 50 sounds like something big not correct . Wrong flote bole on choke carb may be . reed pettles split or broke . stator plate gon wrong with h i end coils not working correct ley .

[norman]

Thanks for the advice guys, Think I will start with the carbs again then work towards the engine. I had been wondering about the crank shaft seals but didn`t want to go there. I will keep you posted on my progress.
Cheers!

[pepsisteve]

you say it wont go over 50mph, so does it go well until then? does it rev ok in the lower gears, speed is a strange description of a fault. compression check would be first on my list, reeds, blocked carb jets, massive air leak but then it would idle rough and struggle to start. it would have to be pretty coked up top end to only do 50mph. i am probably days away from my first test ride on my 250 so stand by!

[norman]

Well....it`s been a while but I think I have solved my problem. After trying several things with the engine, I went back to the carbs and found a dirty jet that I had missed. This had been causing too much fuel to get through the right hand side of the engine.

[soad1110]

Hope your lucks good with that, if so that was a nice simple fix!