2 stroke help
 

High guys

just looking for some help for one of our users on swb he posted the following :

i bought my son his first bike for christmas this year

a tzr125
its an old e reg one

it looks great

but wen he got it he took it round the block no prob

then he parked it up till we sorted his insurance and tax

i got home from work to see the bike in the front garden

ive never seen him looking so down in the face

the bike wouldnt start

i checked the main things still no goo

the weekend after i checked again and the spark wasnt to good
i replaced the plug but no diffrent

i checked the wiring and it was all held together with bits of masking tape
no clips

i stripied it all back spent hours putting new clips on the wires and resealing the loom

but still nothing

i called the local bike breaker and ended up buying
a new source coil a new pulse coil a new generater plate compleate
fitted and also i new cdi unit we had the coild checked on a machine it it was spot on

the spark was great

the bike went lovly

then 2 weeks later it went again
the same things but this time we had a good spark
after hours of striping the carb and finding water droplets in it i blew it out put it back together and it started

ir ran for a week and went again i checked the spark its great
i striped the carb and its spotless

and allset up rite

im stumped now and dont know wat else to do

i cant afford to put it in the shop

so im hoping somone here mite have an idea

my sons back on the bus to collage now

he only road the bike 4 times

its been 3 months now and im out of ideas of wat to tell him could be wrong

so if you can please help

im getting a new carb this weekend if i can find one somone said it mite just be worn out

help if you can pleaseeeeeeeeeeeeeeeeee

shaun





I'm sure some one on here might be able to help.

Thanks

Age

[Edited on 3-4-2006 by AGE996]

Is it a vacuum fuel tap on a TZR, if so it could be passing fuel while standing and filling your crankcase with petrol hence it will not start. Got the same problem on my 350 YPVS at the moment.
Also bad starting can also be down to a leaking LHS crankseal which will pull in air and weaken the mixture, this is more unlikely as it will normally sieze pretty soon after.
Disconnect the fuel hose and put it in a jam jar to see if you get any fuel leaking out is the first thing I would try

Ian

also post here for a wealth of 2T info

http://www.yamaha-rd.com/forum/index...d165c1b50142ce

Big thanks mate I will pass it on.



Big up the DSC

It's not got a vacuum tap on it mate !

He has said when he tries to start it up he puts his hand down by choke lever/button he feels a draught !

anymore ideas

Age

To be honest, especially with old bikes, any kind of armchair diagnosis is going to be difficult. It sounds like he's already covered the usual suspects, cdi, crap in carbs, old plugs etc.
It might just be time to bite the bullet and put it in for repair. Use a reputable 2T specialist if possible. They are fickle things once they start playing up, lets hope it's not the crank seals. Good luck to mate

Could be airleak, whats the inlet rubber like, they crack and perish

My first bike was a H reg TZR125. I have to say there was a real nack to starting it with the kick start and the throttle. I could always start it but every one else used to struggle. When I sold it I spent a few minutes showing the new owner how to do it, it took him a few attempts and then he got the hang of it. I am not saying thats it but it doesnt help. It could be an air leak on a bike that old as the rubbers are bound to be perished in places.:biaggi: