Update On Oilite Bushing/Bearings Conversions of 4 Stroke Belt Drive

[Deleted Member 4613]

After riding the bike just a little, I disassembled the
drive and inspected the oilte bushing and the clutch
bell housing. All very good, and I was surprised how
much oil was deposited on the inside of the housing. The bushing
was releasing oil to the surface. So the initial inspection
is a pass, and now I'll just ride the bike until I feel some
binding or there is some squeaking. So far, so good.

 

[michael whiteman]

Hey Mike......I just started on my trany and have a couple of questions.
1. The amount of oil you found, is it enough to contaminate the clutch shoes ?
2. Would it be OK if you had not inspected and cleaned it ?
3. DISREGARD, I FOUND IT ........ I assume you still have the McMaster Carr P/N for the bushing ?
4. What is the reason your large pulley wobbles ? Bent pulley or poor hole alignment ?
5. Like I expressed in another thread, my cast eccentric housing was machined too large and the two bearings on my output shaft wobble around in the bore. Is this your issue also ? Or did I just get the bad one ? I think they should be a press in fit.

Thank you for sharing all this with us. I'm sure I am not the only one taking advantage of your research.

 

[Deleted Member 4613]

Don't think the oil inside the housing surface is enough to
contaminate the clutch bell. There was no oil inside the
clutch bell when I inspected it. It was operating OK
when I inspected it. I am not sure why there is a slight
wobble in the large pulley. I had one incident when the
kit chain popped off and put stress on the pulley, or it
may have been bent slightly when I assembled the
drive and didn't notice. I'd have to say the overall
manufacturing quailty of these kits is not as high
as Grubee. They're just not made or engineered
to precise standards, otherwise they wouldn't be
using greased bronze bushings. It's extremely
important to use loctite on all the bolts, especially
the one that holds the large pulley, and adjust
the belt tension so it isn't so tight. It's a learning
process with these Chinese kits. I don't have
wobble around the pulley bore as you describe.
You may have a poorly made belt drive.

 

[Chainlube]

Don't think the oil inside the housing surface is enough to
contaminate the clutch bell. There was no oil inside the
clutch bell when I inspected it. It was operating OK
when I inspected it. I am not sure why there is a slight
wobble in the large pulley. I had one incident when the
kit chain popped off and put stress on the pulley, or it
may have been bent slightly when I assembled the
drive and didn't notice. I'd have to say the overall
manufacturing quailty of these kits is not as high
as Grubee. They're just not made or engineered
to precise standards, otherwise they wouldn't be
using greased bronze bushings. It's extremely
important to use loctite on all the bolts, especially
the one that holds the large pulley, and adjust
the belt tension so it isn't so tight. It's a learning
process with these Chinese kits. I don't have
wobble around the pulley bore as you describe.
You may have a poorly made belt drive.

How many hours do you have on it now?

 

[michael whiteman]

Mike......I'm glad you have a housing that was machined correctly for the eccentric. Mine has about .005" slop. I am going to smear some JB Weld around the bore and slide the bearings in. I realize it's a bandaid, but it might work. A better solution would be, bore it out to accept an oversize bearing which sounds expensive. Maybe someday if it comes to that. I'll let ya know how it works out.

I put in my order to McMaster Carr today. A week shipping time from Los Angeles to Oregon tells me they are really swamped. Thanks again for all your research on the subject.

 

[Deleted Member 4613]

I don't have more than two hours on the bike. I've been
swamped with other work. Hope to get on the road
soon. I should add one more note: the oilite bushing is
supposed to be a slip fit over a 15mm shaft, but one of
the two I ordered didn't fit. If it is out-of-spec., McMaster-Carr
will replace it. Sand any burrs off the shaft if they exist.

 

[michael whiteman]

That's some concerning news from Mc /Carr regarding bushing that doesn't fit.

I feel real good about the JB Weld I used today to fill the 0.0025 gap around my bearings. I think it will be just fine. BTW.....I did a search on the quality of the two C&U Chinese ball bearings and found them to be rated very high, which surprised very much. I feel hopeful now on their longevity.

I drilled a hole through my shaft beyond the 10T sprocket allowing me to use a castle nut and cotter pin. If anyone does this be sure to install the factory nut first. This way you can clean the threads as you back it off over the hole.

The allen head cap screw that holds the washer against the large pulley is made from very soft material. I drilled a hole from the center out through one side. I plan to run a safety wire through it and around one of the legs of the pulley. Don't over tighten this bolt. There is no force acting against it, but you still don't want it coming loose. Locktite is good, but this gives one total peace of mind. Moving forward slowly...............

 

[Deleted Member 4613]

I believe these Oilite bushings are heated or sintered and this
process can cause some minor distortion. That's my guess.

 

[michael whiteman]

After receiving my Oilite bushings I have spent countless hours trying different washer thickness and shims to make my clutch bell spin freely with the Allen bolt tightened in the crankshaft. My goal, which I achieved, was to have minimum clearance between the inside vertical surface of the bell and the clutch assembly, and at the same time, to have the end cap under the Allen bolt be as close to the Oilite bushing as possible.

A big concern to me is the quarter inch plus gap between the crankshaft and the narrow ledge on the end cap that goes into the Oilite bushing. Most of the Oilite bushing is not internally supported. With the stock solid brass bushing this might not be such an issue. But with the porous, sintered Oilite bushing might this eventually cause it to separate and crumble? To remedy this one would have to machine a new end cap that reached all the way in and touched the end of the crankshaft. At this time, I am not ready to do this...... but maybe someday.

Next I'll try to make the belt alignment better. The large pulley need some help also. It rubs on the bell. More to come..............

 

[Deleted Member 4613]

No you have it all wrong. I selected the washers to leave just the right amount
of space between the clutch bell and the washer, about 1/16 of an inch, and also
showed that the belt is stable when running because the proximity of the
large pulley to the small one and the tension on the belt. Look at the video
I did showing no movement. The Oilite bushing IS supported by the original
washer which is still used on the shaft. Where did you get the idea that the
bushing is not supported? The entire bushing assembly is tightened down
with the center bolt against the bottom original washer on the motor shaft.
All you needed to do was order the parts I specified and ream the clutch
bell housing to accept the Oilite bushing, assembly the parts on the shaft,
and you're done. The clutch bell spins freely around the OD of the bushing once
the bell housing is reamed to accept the bushing.
Do you understand that the bushing is locked against the motor shaft. The
bushing does not spin around the shaft. The clutch bell spins around the OUTSIDE
of the bushing. The bushing self lubricates under load on its OD surface against
the bell housing. There is no need to do any more invention here. I solved the
problem and did a video to prove the solution.