Honda 50 motors

[scottneidert]

I have two motors I need some information on.
first - I think the motor is an R. It is on a 68 K2, put a different stater so it has the correct number of wires to plug into the correct wire harness. Long story short, trying to put what I think is the correct carburetor on for that year. I have the carb, but the hook up for the throttle is different. Can I change just part of this set up, or do I have to get an entire new cable?

Second motor - on an 87 50r. making a lot of noise, thought it was a sloppy timing chain, tightened that, no help. adjusted the clutch, no help. motor seems to run good. noise goes away when i hold down the gear shifter. Any ideas?

Any help greatly appreciated. Thanks!

 

[b52bombardier1]

The valves on your second engine are probably loose. Set the engine to TDC on the compression stroke (hint - the valves will be loose) on a cold engine and use a .002 inch feeler gauge to set the clearances. Generally speaking, the valves on these engines generally tighten with age so maybe somebody before you set them too loose. That the noise goes away if you depress the shifter is odd. I would probably remove the right side engine cover and see what is going on, just in case it is not your valves. I urge you to buy a set of three Japanese Industrial Standard screwdrivers before you use a Phillips head on those side cover screws. A Phillips screwdriver will cam out of those heads. An impact driver can also be used but I like a JIS #3 for these at:

http://www.mcmaster.com/#53325a61/=rcs2ss

For your first engine, try this for a carb:

*Z50_CARB_OEM CAN_WORK_ON (Z50_76_TO_99) 32MM_PATTERN 1/14M (267K)

or this:

EBay item number 400687684704

I have had quality issues with carbs from Ebay but it is tough to beat the price. These are obviously not factory original carbs but can at least get your engine running while you look for one.

Rick

 

[70sVintageTrikes]

DrATV OPERATES HERE

 

[scottneidert]

Thanks for the info, I can try to adjust the valves.
I did take the side cover off the brake side, and everything looked good, from what I can tell (I do not know much about these). The motor was clean, and no loose parts laying anywhere. I put the cover back on, adjusted the clutch, and the noise was still there. I think the noise might be in the transmission. some times the motor locks up, but if you turn the fly wheel backwards you hear a click then the motor is free. And like I said, holding down the shift lever, the motor sounds prefect. I wonder how bad it is to split this thing and dig into the transmission. :shrug:

Also, on the other motor with the carb issue. I have the correct carb for the bike, but I can not hook up my throttle to it because it is not the correct threads. Can I buy just that part to fit a K2? Or do I need to buy a new cable?

 

[b52bombardier1]

Try this for a topset:

*TOP_SET_FITS LOTS_OF_UNITS SEE_DISCRIPTION 1/14M (71K)

If that does not look right, I probably have one for a 70 or a 90 cc Honda carb in my junk box that I can send you - should fit. It might only need the cap gasket to stop vacuum leaks.

Have you considered that the main clutch nut under the outer clutch cover might be loose? Maybe a bad throwout bearing in the center of the outer clutch cover?

*BEARING THROW_OUT MOST_ALL 50/70/90/110 CC_HONDA'S 1/14A (212C)

If the engine locks up, it might be time to split the cases. You could have a chipped gear tooth. I have also seen broken shift drum stoppers left inside these engines but generally, they stay stuck to the bottom of the engine and do not get jammed up in the gears. There are videos on how to tear down and rebuild these engines - 90 cc engines mostly. But the layout of the engine is largely the same.

Did you clean the black rectangular oil screen while you had the right side cover off? There is also likely a large buildup of sludge under the outer clutch cover in the clutch "slinger" area that should be removed. Too much of a buildup here blocks crankshaft oil flow.

Rick

 

[scottneidert]

Thanks for all the info Rick.

That top set does not look like it will fit a k2, I tried ones from a k3-78 and those are way to big (threaded collar). And I am unable to find a top set that says it will fit a K2. Just have to keep looking. if you have one laying around that you think would fit for me, that would be great. pm me and let me know.

I will check that on the clutch cover, I had it off, but did not check that I guess. I do not really know what I am doing. so its a learning experience.