78 Honda Twinstar CM 185

[cb1ocker]

If you do go to clean the carbs, make sure that you have a set of JIS screwdrivers. All those "Phillips" screws you see on the bike? They aren't Phillips, and regular Phillips screwdrivers make if very easy to strip the heads.

http://www.thegsresources.com/_forum...s-for-the-post!

Nice, thanks!

[cb1ocker]

I have a 200 Twinstar engine and a few miscellaneous parts . I think they are the same animal. Mine had a bent valve, engine ran pretty decent even with that. Let me know if you need anything. It was all good except the head problem. BTW, the carb was in good shape, a major plus.

Will do, thanks!

[Jedz123]

Also, when I twist the throttle I can hear a faint clicking noise where it connects to the carb, but I can't tell wtf is going on...obviously.

I bet the throttle cable disconnected from the slide of the Carburator. It's a VM style carb with the throttle cable connecting to the inner slide directly with a clip (which often falls out or never is reinstalled correctly) from the top of the carburetor... You have to pull the carb anyway but I bet that's the issue there...

[cb1ocker]

Thanks Jedz. On the advice from some fellows over at hondatwins I lubed up the cable real good last night, but it didn't seem to make a difference. I'm going to pull the carb today which will let me know if the cable is disconnected.

Out of all the videos I've watched now on disassembling a carburetor, every single one starts with the carb already out of the bike. If there is still any old gas I can't siphon out of the tank, is it likely to come out when I disconnect the carb? Just wondering what to expect when I remove it.

[Nessism]

If the petcock is working properly it will stop the fuel from flowing when you pull the tank. Just make sure the lever is in the proper position. I'm not sure how that model petcock works so to test you have to do some research.

With the carbs off you will want to remove the floatbowl's and have a look. If there is any grunge then a full tear down is in order. If the carbs look very clean inside the float bowl then you will want to follow up by removing the pilot jets and holding them up to the light to be sure there is no blockage. This should be the absolute minimum you do.

[cb1ocker]

If the petcock is working properly it will stop the fuel from flowing when you pull the tank. Just make sure the lever is in the proper position. I'm not sure how that model petcock works so to test you have to do some research.

With the carbs off you will want to remove the floatbowl's and have a look. If there is any grunge then a full tear down is in order. If the carbs look very clean inside the float bowl then you will want to follow up by removing the pilot jets and holding them up to the light to be sure there is no blockage. This should be the absolute minimum you do.

Awesome thanks. The petcock is in the off position, so hopefully it does its job. I'm planning on doing a full tear down regardless of its condition just to get the experience since I've never done it before. I'll need to do this on my GS550 in the future at some point, so I might as well get some experience on this smaller engine that only has one carb. It also looks like I can buy a brand new replacement carburetor for around $20, so if I completely mess it up at least I have a backup plan

[Nessism]

One carb? Humm. A brand new OEM replacement carb for $20? That would be hard to pass up. You will have to source replacement O-rings and maybe a bowl gasket to do a proper cleaning job and you can easily spend that much with only a minimum of parts.

[cb1ocker]

It's not OEM, but supposedly compatible. I'll keep investigating, it might not work at all.

[Jedz123]

The petcock is a conventional non vaccum operated valve. So there is on/off/reserve. Just make sure she's on off...

Yup those guys only had 1 carb. The Twin star I had had an aftermarket carb as well. I ended up swapping on a a mikuni unit for the quality was better. However I did put a cheap aftermarket carb at first and that cheap carb did work great with the bike. Just make sure the jetting is correct. As I recall I swapped in the main jet from the fouled carb in the bike to the new carb for they were different sizes.

Just a heads up

[cb1ocker]

Got the carb off last night and disassembled. Holy cow these JIS drivers are night and day difference on these screws. The carb didn't have much gunk in it, but the main jet was clogged. Tossed the pieces in a carb dip for an hour or so and then cleaned everything up, made sure all holes were clear using wire and compressed air. Ordered all the replacement seals that I'll put in when they get here.

I'll be ordering a new battery today that should take about a week. Anyone have any advice for verifying I'm getting spark?

[Jedz123]

I'll be ordering a new battery today that should take about a week. Anyone have any advice for verifying I'm getting spark?

Pull the plugs out and install them to the wire. Hold the plug next to the block and turn the engine over. You should see a bright blue arc (or spark). I bet it's fine make sure it's 6 volt battery too, pretty damn sure mine was 6V.

[cb1ocker]

Awesome,thanks. Yeah, it's definitely a 6V system. Should the kickstart produce a spark the same as the starter switch?

[Jedz123]

Awesome,thanks. Yeah, it's definitely a 6V system. Should the kickstart produce a spark the same as the starter switch?

It should... What I would do is remove both plugs in turn not allowing any pressure to build in the cylinders making the engine turn over very easily by hand. Just have a buddy help turn the engine over (you can juggle and turn the kick start and hold the plug wire) but you should see a spark as you turn the engine over.
Good Luck! I did have my battery go flat once and I kicked started it on a dead battery so I can't see why there shouldn't be any spark.

GOOD LUCK!!

[cb1ocker]

Probably a noob question, but is there something specific I need to do to keep pressure from building in the cylinders when I pull the plugs?

[Big Rich]

With the spark plug (s) removed, you can't build pressure in the cylinders.