1972 Honda SL125 - won't rev above 2000rpm

[Noel]

Float level???
or out of left field,
My xl250 was miss behaving intermitently coffing and farting as you discribed and what i think fixed it
 was that I replaced the insulating washers on the points where the wire to the coil attaches ,i'm thinking the spark was short
circuiting,
Have also heard about none genuine points bouncing as suggested earlier.

although it sounds like a fuel issue I would not be suprised if it is weak spark when engine comes under" fuel load".

[Slakewell]

Remove the carby and run the fuel line just in front of the manifold so the end hangs in front< spray some start you bastard in the manifold and turn on fuel and start. It should rev like bastard. If it dosen't it's not a fuel/air problem.

[TT5 Matt]

yeah thats my way of checking whever ive got a fuel or spark problem or if its even going to go and on brush cutters/chain saws whever the carb is pumping fuel and saves alot of time

[Tim754]

  Damn another one slips from my clutching ,sleazy grasp!!!! Cheers Tim754  If you need any parts I may have it/them

[matcho mick]

didja check the resistance in the plug cap?,or just stick the lead straight on the plug sans cap,high resistance would let it idle,but not rev,

[Colin Jay]

I was able to get down to the spray painter last week and pickup the body work for the SL.

Had a bit of free time on Sunday (wife working) so I managed to get the bits onto the bike;





I now looks real pretty, pity it still doesn't run properly.

CJ

[Tim754]

YUM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Rossvickicampbell]

looks excellent - brings back memories - you will get there - keep us posted.

[Mick D]

Ahhh, that's made my day
Pretty all right, looks like you have just come from Frasers in the day,
So many memories

I used to service/ repair and build a hell of a lot of these in my younger days.
Pursue the cheapest rational for fault finding.
I do remember a good battery was essential on these, I used to just try a new 6V dolphin torch battery to eliminate that question.

No doubt you replaced the coil mounted condenser under the tank. Dirt cheap and there is no way the very old original one could be considered as reliable even if it did static test ok for one store and discharge. No doubt your earths and connections are clean.

I have serviced so many bikes with similar symptoms over the years. Always been told, yeap the carby has been cleaned, several times. Then removed the needle jet only to find in the vast majority of cases encrusted or partially blocked with crud and shellacs built up from old dried out fuels and sometimes collapsed air filter material in the cavity around the emulsion tube section and air feed to it etc. Very common.

What a few have suggested,,,,,remove the air box and rubber,,,,then while running, direct fuel into the throat with a plastic syringe while opening the slide. If you get a good rev on? look no further.

No doubt the little plate between the bottom of the slide return spring an needle circlip is fitted?

Goood luck,, at least its good enough for just plain starring at

Beautiful  save.

[80-85 husky]

what a great little trailbike they were. that's a real Gem...
 ol mate had a 100 and the fork drain plugs were stripped by the POS that had it before him...we were 14 - 15 had noooo idea about all this stuff. read a magazine (trail and track) "replace your fork oil" so we did and of course the plugs wouldn't tighten up....what do you do? "araldite it"
It was fine till I jumped into the empty dam and two steel rods appeared next to me with a funny "sploooort" noise...didn't handle too well after that.

[Colin Jay]

A couple of pictures from the SL's past life.

Yes, many sins / crimes were committed in the 1980's, and they were not limited to fashion and hair styles.



Hopefully, the end result of this restoration will see me absolved of some of my previous sins.

Somewhere in the early 1990’s it was put back to original condition. It sat around in my parents shed and saw a bit of use C:1994 when I used it to teach my daughter to ride a motorcycle.



It then went back to the back of the shed and eventually moved from the parents shed to my shed when I left the Navy in 2003. An like many "shed bikes" it had suffered from being a source of parts for other projects.