done about 8mile on my bike and all was fine then started it up about 3 hours l8r and it was still ok got to about 5mile doing 60 at 8rpm in 4th gear and the bike start lossing power/bogging thought it was petrol so i put it on RES then came to a set of lights and it was trying to cut out so i kept revving it and every time i let it go under 7rpm it was bogging and trying to cut out. it got me home any way and and cut out when i when to go down the box and now it wont start every time i try to kick it it makes a pssshhhhhhh sound and feels low on compression. any ideas ?
Remember of you do that and it's fine you'll need a new he's gasket. Better off with an inspection tool and taking the exhaust off. If something's amiss then taking the barrel off.
Little update manged to drop the engine out the bike today to see what was up with the piston and looks like it needs a new piston and rings with a rebore and it also had deep score marks on the exhuast port. the piston thats in at the min is a 66.50 and wiseco make the upto a 68.00 so i should be able to sort a piston out
Remember to either let the company who rebore buy the piston, or buy the piston and take to them. The rebore needs to be done to the specific piston for clearances sake.
Cant see from the photos as many are blurry but if you can afford to, a rebore wont go a miss. If you're worried about hitting the powervalve because of the large oversize, you could always look at getting the barrel re lined with a fresh bore. PJME do it.
i got it all sorted in the end the piston was badly worn and the little things on the piston that keep the rings in place had came lose allowing the bottom and top rings to move and catch the exhuast port causeing major damge to the exhaust port after driveing it for 2 mile flat out doing 57mph lol and the rod and fly wheel had small movement the mechanic say its not the worst he had see but i thought f**k it and get the lot done in total it cost me £450 for the work done from the best 2 stroke mechanic in newcastle hes been tuneing and fixing 2 strokes for 30year ARMSTRONGS
the list
HEAD SKIMMED
REBORE
68MM WISECO PISTON AND RINGS
WISECO CRANK SHAFT ROD KIT
KYOTO MAIN BEARINGS AND SEALS
REST OF THE ENGINE FLUSHED
GENUINE GASKETS ALL ROUND
-- Edited by DT200R MACCA on Saturday 8th of December 2012 03:57:38 AM
-- Edited by DT200R MACCA on Saturday 8th of December 2012 09:40:54 PM
its all done m8 took him 3 days time he had to wait for the parts and stuff and av done just over 200mile of granny rideing not going past 5k rpm told me after 300 miles to start building the revs up but keep out of the power valve till 500 miles then start giveing it short burst till 600 then ride it normal after that and use minrel oil like you said but up to 600 mile then start useing the good stuff again
its funny how nearly exactly this happened to my re, took it apart yesterday everything was mint for a 10k mile bike apart from it had 1 and a half piston rings and had eaten the top and bottom of the exhaust port, no wonder if felt a little slow hahaha
you should have seen how slow mine was after it tryed cutting out at the lights it couldnt even keep up with a ford escort and yours did that after 10k thats bad that m8 my old 125 engine had 26k on it and it still started 1st kick on its original piston it didnt have no pull in 6th tho probs that worn out
-- Edited by DT200R MACCA on Thursday 13th of December 2012 04:38:22 AM
i took a chunk out my exhaust port and took a bigger chuck out of my piston, and rode it another 2 miles down the road an wouldn't go over about 10mph, as soon as i let throttle off the bike cut out, didn't try an start it again because i knew what happened lol
