Engine Trouble Another power loss story

It pays to measure the ring end gap with any new set of rings.

Use plenty of oil to soak the new rings, and smear the new cyclinder with oil to.
Then fit new ring, one at a time inside cylinder, (without piston, but AS If it was on piston, and close up the ring carfully not to scratch the bore, to bring the 2 ends together. There is supposed to be a gap, the ends are not suppose to meet. If they do meet, then file bit by bit off the end of the rings.

I would say check with the old cylinder first, practice a bit to avoid scratching the new bore. Or test for end gap with the new rings on the old cylinder first.

If there is no end gap when the new rings are set in the new cyclinder, how would one expect the rings to close up when fitting the new piston etc ?
Snap !
:rolleyes:

Pays to check at least. can't remember off the top what the tolerances were, but I think about .003 or .005 inch, but I'm guessing.
Someone else here might know what the piston ring end gap tolerance is for a HT ?

Some discussion here about the same thing in principle on VW
http://www.volkszone.com/VZi/showthread.php?t=482571
 
Sorry, gasket was on the jug lol, just stuck.

I got the new petcock on, much better flow, still not much better. No news on the head from spooky tooth yet. Going to try a used jug and rings for now, keep it cheap :)

I do have some experience with car engine building, will certainly check the ring gap and adjust as needed. I know these are loose motors, but still, gotta have some sorta tolerance :)

If I do go with a whole replacement, who sells the best 80cc replacement? Spooky Tooth has one for $160.
 
I have the Black Slanthead 80cc kit from Zoom. $145 free shipping to Wash St at least. If it's more to Hawaii you deserve it (read I wish I lived there). Anyway, I've had exellent luck with my motor so far. Most I've talked to with this motor have also. I did find it likes a cold plug. I'm using a NGK b7hs. Also Thatsdax has a motor with no kit for like 80 bucks. Since you already have a slanthead coming. Maybe a better way to go. I've heard good stuff about their motors too. Good Luck Man

Ok I looked dax is soldout, and the price was 88 and 14 to ship. Gasbike has some in stock for 89 didn't see the shipping cost.
 
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Well, this bike was a super cheap beach cruiser meant mainly as an experiment. I drilled the main tube to mount the engine. In my investigation, I found the stud had snapped, so I ordered a SBP mount. I had wrapped the frame nice with some heavy rubber. I had some time tonight, and decided to mount it up and see how it worked. When I pulled the rubber off, I was shocked to see the hole caved in, and nearly 1/2 the tube cracked. I did mount the adapter just to see how it goes, and it is the tightest the engine has ever been! It seemed to run much smoother LOL. I got about 1500 miles out of the cheap bike, so I can not complain. I do have a good friend who is a welder/metal fabricator, I might have him fab up a repair with a built in mount, but this is a darn cheap bike LOL. Might be better to let her go :) I took the bike for a quick spin, and it sure was smoother, and seemed to have more power without all the vibration.

I did order the zoom kit up, should be here next week. I have a good old Trek 4300 that was my pedal commuter for about 8 years. It will be much lighter than the cheap beach cruiser, has a suspension fork, and can also be converted to disc brakes. :cool: My plan is to build the Trek with the slant motor and a shifter kit :) Thank should be a NICE commuter.




( I do realize this is upside down on the mount LOL, it was the first test fit!)
 
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bike swap

H.ED; Your trek looks real similar to my ROYCE UNION. The cables run on top of the top tube, and the tubes are larger in dia. than the seat post tube. I had to make my own front engine mount, and use flat stock and coupler nuts to mount the tank. (mods took 2 days of spare time after work "a couple hours total"). I'm still doing mods and adding a thing or two as I go.:D:unsure: I still have not figured out how to post pics yet:confused: good luck on your swap!
 
Does sound just like mine! I hear some people have gotten away with putting a sheath on the cables, but I will prob do a spacer with a channel like you said :)
 
Got the Trek built and running great, and decided to fix up the old crusier too. I fixed the power loss, my friend 5-7 had two brand new motors in his shed LOL. Tossed one of thos on there and it is back over 30 MPH at cruise! I am going to have a welding buddy of mine take a look at fixing the frame this weekend :)
 
First down & goal to go "FASTER"

Glad you got every thing together and going good!!!:cool: My Royce Union has it good days & fair days, it was having a good day last Sunday on a "find a new fishing hole" trip. At 32 mph according to my Schwinn speed-o,:D the bike did not hold the gravel road as well as I wanted it to, (+ a 30 lbs back pack) I finally went down.:eek: (It was bound to happen sooner or later):whistle: I push every thing to the limit!:giggle: Any way I still love these things!! I really need to post this on "safe speed" thread. I'll say safe speed is 20ft per sec. slower than crash dummy speed:rolleyes: Don't know what that is in mph (don't have a calculator handy). Just remember if your having fun the pain doesn't matter!:rolleyes:
 
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