RM100 Won't start

[blacktopspirit]

Hi guys

I'll shorten this story as much as possible

I bought an RM100 looks like an early 80's, it's missing the kick start so I tried to roll start it, after a few goes it fired up and ran for a short time before it just died in the ass, now that I know I have a running bike I thought next step pull the Mikuni VM carby off and give it a full clean, and it needed it!!! there was a strong build up of shit in the bowl and also a greasy film in the fuel lines.

I got the carby back on and and first time with ease it fired up! but it revved higher and higher until my mate shit himself and pulled the lead out of the coil! he gave it a quick fix with a screw and some solder, and we had full spark, I would even go as far as to say great spark! but since this happened I can't seem to even get it close to starting.

it feels like it has plenty of compression, it getting fuel (maybe to much?), it's getting air, it's getting spark.

the only 2 things I can think of are flooding? or carby settings?

my dill hole mate decided he could "reset" the carb and now he fiddled with all the screws

so is there a standard setting I can set the carb just I can start it?

I turned the idle screw all the way in, and the mixture screw 2.5 turns in from all the way out???


any help would be greatly appreciated

cheers
Brendan

[pmc57]

The idle screw should not be screwed all the way in, that will only makes it rev more, and if you've set the mixture screw 2.5 turns in from all the way out then the idle mixture is set way too much lean which will and may have caused it to rev it's nut off. Mixture screw should be 1.5 turns out from the fully IN position. Leave the idle screw alone until you get everything else sorted, it's only to adjust the idle speed, but keep it screwed  a few turns out until you're ready to adjust the idle.
Have a look where the idle screw contacts the carby slide. You will notice that the more it's screwed in, the higher it pushes the carby slide up, puching the slide up results in the engine to rev higher, normally.

[blacktopspirit]

thanks heaps for the help I'll give it a go this weekend 

[Ji Gantor]

When you screw the mixture screw all the way in be gentle at the end when it seats. If you over tighten you will damage it. Just keep a steady turn going until it just stops then back it out the 1.5 turns.


Ji

[lukeb1961]

may have fouled-up the float-level and/or needle & seat too.

RM100B manual (also uses the VM30SS) shows how to measure that.
http://cid-407d7ef0965d3991.skydrive.live.com/browse.aspx/Racing%20Model/RM%20Owners%20Manuals

[DR]

Quote "some of the worlds biggest mistakes were made with the best of intentions' gotta love mates sometimes eh, first things first, fit a killswitch!

[lukeb1961]

It is odd how often I hear from mates with this sort of issue. Why is it that the kill switch seems to go missing so often??? The things cost what, $9 or something!

[DR]

The things cost what, $9 or something!

or $900 for a genuine red button PE killswitch

but yes, even a wire to ground on the bars is better than going anywhere near the plug cap and risking the 60 zillion volt charge that near alway ensues..call me a wimp but tazers pale in comparison! my heart needs to keep beating for a little while longer yet

[blacktopspirit]

yeah kill switch is one of my other issues

It has one, it just doesn't work!

I figured the wire was earthing somewhere, so traced it all and fixed a couple of dodgy points, but it still doesn't work, tested the switch with a test light and it's all fine. so my next step is running all new wire!

and am I right in thinking it should be hooked up to the black and yellow wire?

When you screw the mixture screw all the way in be gentle at the end when it seats. If you over tighten you will damage it. Just keep a steady turn going until it just stops then back it out the 1.5 turns.

thanks for the advice 

[blacktopspirit]

update

I got it going, but it wouldn't idle, no matter if the idle screw was all the way in or all the way out it didn't change anything, but it does move the piston in the carby so I would assume it would be working...

any way could only get it running without air filter, so I need a new one of those, and once we started playing around with the air/fuel it wouldn't run again.

so I'm just gonna buy a new plug, filter and maybe a kit for the carb, if it doesn't run after that I'll be selling it

I spend to much time on things that don't work

[frostype400]

but did you clean the carby a jet could be blocked the idle screw not making a difference points to that what happened could you rev it or did it die id say you have carby problems selling could fix the problems all together thanks Michael.

[blacktopspirit]

I cleaned the carb last time and I cleaned it again today, I could definitely rev it, I could keep it running just by a touch of throttle, but it would die as soon as you where off the throttle, come to think of it niether the air/fuel mixture or the idle screw made much of a difference.

[frostype400]

thats odd maybe it could be ridden out how far in did you screw air fuel screw in because i usually start by going right in then one and a half turns back??i haven't ridden an rm100 i wonder if they like idling or need to be on the pipe alot?

[oldyzman]

Mate is it possible that when you put the carby slide back in that the slide groove did'nt line up with the the little peg inside the carb. therefore holding the thing on full throttle. This happened to me on an old TS approx 25 years ago. you have to spin the carby slide a bit to line it up and sometimes the needle has a bit of trouble lining up too-same result
Cheers Brett

[blacktopspirit]

Mate is it possible that when you put the carby slide back in that the slide groove did'nt line up with the the little peg inside the carb. therefore holding the thing on full throttle. This happened to me on an old TS approx 25 years ago. you have to spin the carby slide a bit to line it up and sometimes the needle has a bit of trouble lining up too-same result
Cheers Brett

I'm pretty sure it was all aligned correctly, as it seemed to only go in one way, and the needle was a pain to line up as well but I'm sure I got it all together right

there's a Carb on Ebay, I might just buy that if it's cheap enough.