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A compilation of Sportster fixes
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| Garage | OSARM | Repair | Smörg |
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 Honing the transmission mainshaft bearing
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 Here you can see another mistake. I chucked the proper line hone into a drill and used forward and reverse to cut the race. Turns out I cut too much, and made the bearing so oversize, even the largest oversize rollers did not tighten up the mainshaft. Use the handcrank. I was stuck a bit since I felt I had to take the bell shape out of the bearing. In most cases, you are just trying to align the trapdoor bearing and this one. A few turns is all it might take. I later replaced this bearing sleeve when this loose mainshaft caused the countershaft bearing to get eaten up. Yeah, it really was that loose. I would guess 10 or 20 thousandths. The mainshaft is not supposed to go "thunk thunk" when you wiggle it. For the grinding compound I used Clover Compound. This tin came in a package of two, "Coarse" and "Fine". (duplex cans E120/A280) I was careful enough to use the fine compound. I did not want the hassle of contaminating the hone with two types of compound, and having to clean the hone when I changed over. |
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 OK, so a little compound, you don't need much and if its dry you can add some 60-weight oil or whatever you have laying around the garage.  You expand the hone by turning threaded collars at each end. You use a tool similar to a shock absorber adjuster. You can see it along side my thumb. You can see an identical collar on the other side of the hone with little holes around its periphery  |
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where the tool engages. The smudges on the shaft are not lapping compound, that is anti-seize. Here I am using a drift to tap in the hone guide that comes with hone. It is generally wrong to hammer on a bearing race. This one is a bit lighter than a press fit, it's OK as long as you use a rubber mallet. Duncan Keller taught me the real secret is to have the trap door out and hold it in your hand.  |
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| The combination of rubber mallet and having the trap door unsupported allows you to get away with it. The same policy applies with the clutch gear that goes in this bearing. Its OK to tap it in if you are gentle with it. You can see in the previous picture that the hone is now squaring off the bearing race. It is silvery across more of the depth than the first picture above. Unfortunately, I was such a hack using the brake hone before, that by the time I got a nice uniform lapped appearance across the whole surface of the bearing race, the race was way oversize, even for the oversize rollers you can buy. The real solution then is to push out the race and instal a new one. Then just touch that race with the hone to align-bore it to the trap door. I did end up doing that, and will link to it when I get it posted.  You can expand the hone a bit as you grind away. Once again do not use a drill like I did, the hand crank is plenty fast and you won't overbore it like I did. |
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 In theory the hone will expand the same if you tighten it from either end. I like to reef it in a bit on both sides. Go slow. You can see how the sheetmetal tool engages the holes in the hone collar. Don't use a drill.  |
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| So there you have it, a pretty esoteric fix, but the drag racers tell me this is critical to keep from blowing up transmissions. Oh, and a great tip from the XL Forum. Don't use grease to hold the 23 rollers in place as you try to get the tranny back in. Just don't install the circular clip, slap the tranny in, then add the rollers, the washer and the snap ring from the outside. Its a big job since the transmission work is more consuming than a top end job, You have to take the primary completely apart and you usually have to take at least the front exhaust pipe off to get the sprocket cover. You may have noticed my 1977 Sporty does not look like any other. I cut off the starter pocket and had a pal weld up the case and primary cover. I installed a dry clutch setup running wet with Barnett fibers and springs. I got tired of sprocket covers breaking, so I made a steel perch for the kickstarter and made my own clutch mechanism for the dry clutch setup. That was a bit of a failure since it still does not have enough leverage and the clutch pull is pretty stiff. One nice thing is I can get the tranny sprocket off without breaking the chain, that is really nice. I unhooked the kickstarter for this so it just hangs down. The other "custom" thing is the rear brake. I welded on early model peg mounts so I can run the 1975-76 peg with the brake stuff. The 1977 rear break is a bit kludged for me. I don't like this setup much better, the cable keeps breaking. For my money the mechanical shaft rear break was the best setup. I will be thinking on a way to adapt that to a right-side-brake bike like the 1977. |
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As of 2015 the only supplier for the line hone lapping tool is
Eastern Motorcycle Parts. The
pictures go with the table on the last page. The pictures go with the table on the last page. |
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You need A-96710-77 unless you already want or own the crankcase
lapping tools. In that case you can buy the transmission lap separately. The
pictures go with the table on the last page. The pictures go with the table on the last page. |
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