Bike runs good,but won't start

[koimre]

Hi all!

My bike is a 1998 RM250

It won't kick start,either its cold or hot!!!
Changed spark plug NGK B8EIX/I do have spark/,Fresh fuel.
Also very hard to push start too.
Once started it idles fine and runs fine.

Thanks for any advice.

 

[RM_guy]

Check the reeds. Chipped or poor sealing reeds are usually why a bike won't start. There should be no cracks or gaps with the reed block.

 

[koimre]

THX for the quick reply.
I'm not too familiar with the reeds.
I took it out,it seems to be OK.No cracks,But noticed the inside part is flat/shiny/,outside has texture on it.
I don't know where to check the gaps?
It was very wet /fuel/when i took it out.I guess it shouldn't be.
If the carb needs to be cleaned,than it wouldn't run fine.Am i right?
THX

 

[jason33]

if the reeds are wore (gap is to big) it will let too much fuel in ,flooding the bike,and making it hard to start
i suggest a set of carbonfiber reeds -either fmf,or pro circuit ,there a great product ,just follow directions, you can even call fmf, for help on jetting,if you have there pipe ,and silencer,there really cool about helping ppl

 

[schmanman]

boysen reeds are a good product too!

 

[RM_guy]

if the reeds are wore (gap is to big) it will let too much fuel in ,flooding the bike,and making it hard to start...

Not quite. Reeds that don't seal well or have cracks will allow blow back when trying to start and a loss of power in the low end of the power band. Blow back prevents the fuel from flowing up into the combustion chamber and that's why it is hard to start. You will also see a loss of low end power.

The gap we are referring to is between the reeds and the reed cage. They naturally rest against the cage and should be sprung against the cage fairly tight. If they are shiny as you say then they have been in there for a while and the spring has weakened too much. They open and close a lot and will wear out over time even if they aren't cracked.

 

[koimre]

Thank you very much for everybody!
I learned a lot from you guys.
Yes,the reeds are not very tight against the cage,altough there is no gap.
I'll head to the shop for new reeds.
I'll post if the bike is back together.

 

[2strokerfun]

I'd tried cleaning the carb, paying close attention to the pilot jet, before stampeding straight towards the parts store.