problems starting cold

[125SMash]

got the bike back from the dealer.

no problems starting it there.
the next day, again same problems.
it just doesnt start.

the battery is 160cca (whihc is more tahn enough for this bike),
the sparkplugs should be fine,
what else could be tweaked/adjusted/replaced to help it start in weather 20-30 F ?

[DAVID THOMPSON]

hello

sounds like the choke is not working like it is supposed to

mine started like it should at -5deg f the other day

ar dave rt125 in wv usa

[125SMash]

hello dave,

i remember you mentioning excellent starting performance on your 125RT
i installed the 160CCA battery you recomended, without problems (thanks!)

the choke wheel does feel a little weird actually.
though i hadnt even considered it being at falt until now.

i'll look into it tomorrow..

[125SMash]

i got some good news from the original dealer;
the service manual i asked for is on its way to him,
so i should be receiving, and using it to diagnose the choke shortly.

meanwhile, i wondered if you can give me some thoughts on this symptom.
when trying to start in 20-30F the noise consists of the electric motor, and some thumping of the engine as it tries to start.
at temperatures lower than that, electrioc starter motor is the only noise it makes, not even a hint of engine thumping.

does this add, take away or does nothing to the theory of the choke as being the culprit?

[phlat65]

I don't know the arcitecture of the 125 engine, but on my old honda, the kick start is on the trans, so when the engine is hard to turn, the clutch will slip, and not turn over the engine. will it crank with the clutch in?? if it does, then mmaybe the drive on the starter is slipping. try bumping the engine over in gear, then try the starter again. Piston engines usually stop in the same position every time, (this is why aircraft props always end up in the same position) so maybe the piston is sticking to the cylinder wall when the condensation inside the engine freezes. try those....

[DAVID THOMPSON]

hay
smash go to the yahoo MZOG site and read the files section

file is called rt125 broken part warning
copy this and show it to your dealer
the sprag clutch on the starter is dieing
parts book
page
mo7 L7 parts 6 7 8 9 but it comes as one peice number nine
mz part number 9= 3743065005
your dealer needs to talk to me before they try to fix this
as i have done it and there are things that need to be done or more problems will be caused i will be more than glad to talk to him or his
workers
he can e mail me at wd8cyv@yahoo.com and i can tell
him what i found in mine when it went out
tell him to send me a phone number and a good time to call him
ar dave rt125 in wv usa
spraga freewheela

[125SMash]

I don't know the arcitecture of the 125 engine, but on my old honda, the kick start is on the trans, so when the engine is hard to turn, the clutch will slip, and not turn over the engine. will it crank with the clutch in?? if it does, then mmaybe the drive on the starter is slipping. try bumping the engine over in gear, then try the starter again. Piston engines usually stop in the same position every time, (this is why aircraft props always end up in the same position) so maybe the piston is sticking to the cylinder wall when the condensation inside the engine freezes. try those....

this sounds like a possibility. i'm gonna try that

[125SMash]

heya david,

i checekd out the mzog section.
i've read that article before, but it sounds to me if the starter was bust, then the bike would not start at all, warm or cold, and mine still starts fine if it was in room temperature long enough.

i appreciate your offer of contact and advice, i dont know how it is in WV, but NY dealers are not that receptive of outside advice
hopefully i can work this out on my own without having to transport it to him again..

thanks again

hay
smash go to the yahoo MZOG site and read the files section

file is called rt125 broken part warning
copy this and show it to your dealer
the sprag clutch on the starter is dieing
parts book
page
mo7 L7 parts 6 7 8 9 but it comes as one peice number nine
mz part number 9= 3743065005
your dealer needs to talk to me before they try to fix this
as i have done it and there are things that need to be done or more problems will be caused i will be more than glad to talk to him or his
workers
he can e mail me at wd8cyv@yahoo.com and i can tell
him what i found in mine when it went out
tell him to send me a phone number and a good time to call him
ar dave rt125 in wv usa

[tjchick]

Hi Guys,

I got my SM last Friday, and had a similar problem. A mate of mine who is a mechanic, sat on it, twiddled the idle speed on the carb a tiny bit up, and now it starts fine!

I'm really pleased with the bike - so much better than the Yam SR125 that just failed its MOT - front and rear suspension had no damping,
and the exhaust was all holes!

This post is so old I guess you may have figured this out though?

Cheers,
Tim

[DAVID THOMPSON]

problem is not compleatly solved
do a search for freewheel and read the hits

and i am installing 2 batterys
one to crank and one to run the ingition box
as mine is a beast in cold wx even after playing with carb cleaning

and the new owner they dont start to get loose and run good
till after 4000 miles so do the breakin and and then let howl
down the road

[F0ul_Oli]

Don't know if this might be of help to you but I had a similar problem recently.
The bike was turning but not starting and I couldn't work out what the problem was.

Out of desperation, I opened the tank, and it started on the next button press. Not sure if it was a vacuum in the tank that was the problem, but I got my bike started!!

Hope it helps!

F0ul Oli