HS50 flames out exhaust

#21
Hi guys- just a follow-up. I got the bike finished and the engine is just not right. I have a feeling that when I pulled the case cover to remove the governor that maybe I got the cam a tooth off (retarded).

Before I tear into the motor again I wanted to see if any of you have done this before and if the motor will actually run this way. It's really lazy and lethargic and won't really rev very well. It needs a ton of fuel to keep running. My little 3hp side popper is way more powerful and responsive than this hs50 which should not be!

Does this sound like a potential or typical screw up?

Thanks
Matt
 

markus

Well-Known Member
#22
Hi guys- just a follow-up. I got the bike finished and the engine is just not right. I have a feeling that when I pulled the case cover to remove the governor that maybe I got the cam a tooth off (retarded).

Before I tear into the motor again I wanted to see if any of you have done this before and if the motor will actually run this way. It's really lazy and lethargic and won't really rev very well. It needs a ton of fuel to keep running. My little 3hp side popper is way more powerful and responsive than this hs50 which should not be!

Does this sound like a potential or typical screw up?

Thanks
Matt
was looking at your build thread.......
your cut off PTO camshaft is not interfering with the clutch guard is it? It looks like its right ont in in some of the pics. Would be easy to spot since paint will be worn off. Remember the cam and crank have a lot of endplay on bushing engines so they flop back and forth under load. If that is happening or happened it would cause a bind. If it was a strong enough grab/bind, It WILL move the gear on the crankshaft since they are simply pressed on the crank in that size engine. Also by using what looks like RTV/form a gasket sealer you have actually increased the endplay and are allowing more movement (and made a hell of a mess for yourself if you have to open up the engine).
 
#23
was looking at your build thread.......
your cut off PTO camshaft is not interfering with the clutch guard is it? It looks like its right ont in in some of the pics. Would be easy to spot since paint will be worn off. Remember the cam and crank have a lot of endplay on bushing engines so they flop back and forth under load. If that is happening or happened it would cause a bind. If it was a strong enough grab/bind, It WILL move the gear on the crankshaft since they are simply pressed on the crank in that size engine. Also by using what looks like RTV/form a gasket sealer you have actually increased the endplay and are allowing more movement (and made a hell of a mess for yourself if you have to open up the engine).
It's close to the cam end but not touching. I have sealed up another motor the same way with no issues as well- it's a pretty thin bead I have there. I will probably crack the case back open to check the cam. Assuming the engine will run with the cam off one tooth, then it would make sense to me what I'm seeing with it. Compression and spark are good, new carb, new gas, and the timing gap is set up correct so I must have something else off in there....
 

I74

Well-Known Member
#25
was looking at your build thread.......
your cut off PTO camshaft is not interfering with the clutch guard is it? It looks like its right ont in in some of the pics. Would be easy to spot since paint will be worn off. Remember the cam and crank have a lot of endplay on bushing engines so they flop back and forth under load. If that is happening or happened it would cause a bind. If it was a strong enough grab/bind, It WILL move the gear on the crankshaft since they are simply pressed on the crank in that size engine. Also by using what looks like RTV/form a gasket sealer you have actually increased the endplay and are allowing more movement (and made a hell of a mess for yourself if you have to open up the engine).
You figure with RTV ect., What you see oozed out side, is going to be the same ''or more'' on the inside.
Eventually the stuff will come off from oil saturation ect. & start plugging up & or restricting oil pathways ect. ''Not good''.:confused:
I have seen to many Mechanics ect. through out the years, just go western on the stuff, & not even think about the potential harm it can do.
Still see guys today in factory car dealerships doing it like that.:rolleyes:

I don't use the stuff hardly at all, & if I do,, l will use the real expensive white/grey stuff, that they use at the assembly plants.
A decent substitute is called ''Right stuff''. It's black, & usually comes in a cheez wiz can ect..

The blue & orange silicone is no good @ all, regardless what you use it on.

When you do use sealer, always run just a ''very'' small bead, towards the ''outside'' matting surface,, less than 1/2 the width.;)
 

markus

Well-Known Member
#26
I didn’t know these would start/run off a tooth but weird things happen all the time lol

I never tried, so I dont know. the one I found with a moved crank gear had some junk run through the cam bore causing it to bind when it came in, so I inspected everything really carefully and spotted it thankfully when comparing it to another HS crank before using it in another engine......I am betting I would have been pulling my hair out, well whats left of it anyway, trying to figure out what was going on had I put in another engine!!!
 
#28
Well- I pulled the cover off, and the cam moved a lot when I did it, so I couldn't tell if it was off or not. I scraped off the rtv and replaced the cover with a proper gasket. Verified cam is in the correct position. Still runs like crap. Idles well but won't build rpm- really lazy. Pulled the front cover and the magneto gap is still good. Might throw another carb on it just to try. Otherwise, maybe the mag is going bad? I assume they just go bad and stop working, rather than just reducing performance. It really just runs like the timing needs way more advance.
 
#31
All good. No key twisting.
Well, this is embarrassing.... After swapping out the carb again and a second ignition module I had around, it turns out the flywheel key was sheared after all. Of course with all the pulling and pulling, I broke the recoil. So, new recoil on order and I stole a key from a spare hsk50 parts motor I had around. I'll see if I can fire it up tomorrow....
 
#33
Success!! Well, it was definitely the key. I replaced it and proceeded to shear it again, so I stole another key from a spare motor and then lapped the flywheel to the shaft with valve grinding compound, cleaned it up and put it back together this time with the proper torque on the nut. I think the first time, I just hit the nut with my DeWalt driver and it was not enough torque to seat it well on the crankshaft.

Now it starts on the first pull and the throttle is real snappy. I went for a rip down the street and back and it is a really nice linear power band. It's not as heart pounding as my predator 212 toad, but way more exciting than my 3hp side popper! While I was trouble shooting, I filed the threads near the head of the bolts for the ignition module and was able to give it a bit more advance. I also removed the starter gear to save some weight.

I'll see if I can post video.
 
#35
cool you got it running. it may not feel like a built 212,but still a lot fun to ride. video would be nice.:scooter:
I'll try to figure out how to post video. Attaching an mp4 didn't work. And thanks for the tip on filing the threads for the ignition module to adjust advance. Worked well!
 

delray

Well-Known Member
#36
I'll try to figure out how to post video. Attaching an mp4 didn't work. And thanks for the tip on filing the threads for the ignition module to adjust advance. Worked well!
not real big into computers and all, maybe someone can help you with your problem. If you have youtube channel? you can down load it though it maybe and then play it.
now your next flathead going to have a billet rod, Tecumseh hot coil(advance the timing more)22mm carb etc......:scooter:
 
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