Bonneville America Forums Forums General Motorcycle Forums Other Bikes Twinstar Starting Problem

My fiancee just bought a 1980 Honda CM200T Twinstar as a starter bike. The darn thing won't start. I'm 98% sure I know what is wrong but thought I'd run the situation by the learned collective here to see if we jibe on the possible problem.
Charged the battery, engine turns over with the electric start. Pulled both plugs and grounded them against the jugs and cranked the engine - Nice spark on the plugs. Pulled the gas inlet hose off the carb, gas flows freely. Sprayed a bit of Carb & Choke cleaner in the airbox, hit the start button, after a few cranks the motor comes to life for a few seconds then shuts down.
This isn't the best bike in the world, but it IS a parallel twin and I'd like to get it started for her before the riding season here ends. I'm pretty sure I know what is wrong, what do you think?

Carbs gunked up. Remove, clean, replace.

ditto

I agree, Try fresh petrol in the tank and put the tap to Prime or On if its not suction operated, open the drain screws on the float chamber bowl untill you get fresh petrol running out, close them, clean up the petrol spill
( very important)
It should at least start and run on higher throttle openings. If its rough at idle remove carbs and clean air passages and jets like the guys said.

I would like to thank you all for confirming my thought. I am going to rip that old carby out and give it a thorough cleaning tonight after work. Plus I'll flush the tank for any loose debris. I ordered a carb kit for it last night but it'll take a few days to get here and my fiancee' wants to ride this weekend.
Ya know, this little bike is ok. When the fiancee' upgrades to my Speedy in a year, I'm thinking about making it into a cafe racer. Could be a cool little project.

You need to visit Carpy when you're ready to start the cafe project.

Very Cool. Thanks for the link. Here's what it looks like now...

Mini apehangers...what a hoot! Still, it looks like it'd be a fun scoot (and you gotta dig the megaphone exhaust).

I'd be surprised if you even need carb kits or to drain the tank. In my experience, the jets tend to gum up as do the internal passages,(note: varnish smell). I believe you'll find 2 jets and a power valve once you remove the bowl. Simply remove each and spray carb cleaner into passages,blow compressed air into passage. Clean each jet w/ carb clean and run a welding tip cleaner trough each cross drilled orafice as well as through the jet itself. your bike will run like new.
Good luck,Paul

The precursor to the Rebel. Both great bikes and rock solid....

Chances are good that the T fitting between the carbs where the gas hose attaches is full of residue. Happened to the OL's training wheels bike too, that's why Triumph uses the secret filter. An inline filter won't help because the gunk there is the remains of gas evaporating in the hose.
Once cleaned out, the bike should be run with the gas shut off to empty out the hose anytime it's to be left sitting more than a couple of days.

The gas in it was pretty much varnish. Took the carb (just one of them, Greybeard) apart and did a good cleaning job on it. It wasn't bad at all. No gunk, no clogs. Could be something was stuck and wasn't working properly, who knows - I didn't find anything obviously wrong. Sprayed it down with carb cleaner and blew it out with my compressor. Piece of cake. Well, except for one thing - I neglected to pull the small, tiny, (miniscule even) needle jet before I unleashed the air hose on it. I do believe that the needle jet was propelled out of the carb at a very high rate of speed and headed to parts unknown.

So, I went on'line and located a carb kit for it (IN CANADA!!!) and it'll take a few weeks to get here. Lesson learned - Make sure to remove ALL the parts from the carb body before blowing it out with high pressure air.

I'll let you know how it ends up if the carb kit ever gets here.

Might take a closer look at the float valve if it was full of varnish. That's a simple part but critical to success and really likes to be spotlessly clean.