Hello everyone,

I have come soliciting some advice - I have a highly modified evo (stage 4 or 5, depending on your definitions). It was putting out so much power that it was twisting the primary off the crank (evidence by a leak of primary fluid from that area with dirt buildup), and causing the good old inner primary bearing twist and seal leak from too much torque scenarios on my daily commutes. The bike has 80,000 miles on it, 40,000mi put on by the PO and 40,000 put on me with my stage 4 rebuild about 10-15,000 ago.

While I have the high torque double row ball bearing replacement coming to replace the stock inner primary bearing and take care of that issue - I recently discovered a problem with the left side crank case - the o-ring that sits on the shoulder of the crankcase specifically. Where that Oring sits on the crankcase is cracked about halfway around following the inner corner. Photo is the upper right bolt location for the primary. Crack goes from there to the bottom bolt on the same said.

Is this a future fragmentation grenade waiting to go off?

 

OK, well that sucks.

Here are some options
1. New cases
2. Have lip fixed correctly with steel insert. Expensive but save case vin #s
3. Run belt primary
4. JB weld
5. James crankcase saver kit

 

Is the bike a dyna?

 

That will happen on a built Evo. You best option is to have if welded.. or you can get a hole new belt drive primary then you won't need the lip our the seal.. or as stated, replace the case but that can get real expensive.. Who did you motor build and what exactly does it consist of?

 

I doubt that was a "too much power" thing... unless yer doin 8's in the quarter..and switching to a Belt will Not make the problem better...that is Most probably from having used the wrong O-ring [there are 2] or.. improper assembly.. ie Prying on the lip..even via the inner primary..
For rigidity.. the steel insert "ring" is better than O.E. If done properly.. Case saver gasket is kinda like belt drive... mask the problem.. Weld????? IDK maybe... never worked out well for me... I do Not believe the MoCo offers cases for EVO anymore, so... 3-Bond and proper assembly will get ya thru the Summer.. a steel ring can be inserted next rebuild....

 

I used to love Three Bond/Yamabond/Hondabond for such jobs (and still keep a tube handy) until I found out about 515 flange sealant. Better wetting than silicones and bonds very well. Don't use it on a derby or chain adjuster cover because it holds a bit too well for those and prying them off isn't nice to the edges.

Since the "problem" is cosmetic (oil leaks) rather than structural I don't rush to surgery. I've had a James kit on one Shovel for many years. I'd wait until I tore down the engine for something so minor. It's not hard to put a left side case on a rotary mill table, remove the lip then machine for a repair ring but it's annoying to pull everything else to get the left case off. I wouldn't run a weld bead around it then machine because that recreates the same idiocy. That joint should have been flat, not piloted to a rim, and sealed with an O-ring in a groove in either case or inner primary.

Yep. Thicker isn't better!

 

That's probably the best fix I've heard of... Machining a groove for an o-ring on the inner primary would probably be the easiest and cheapest... Great idea man...

 

No, it's an 96 Electra Glide,

The guys on V-TwinForum pointed me to a gasket that was created to sustitute in for the oring, mating the primary to the crank (crank saver, PN 11125), so thanks for seconding that. I am converting it to a dry primary, so as long my crank seal doesn't fail, it solves my issue of oil leaks! Last time I offered even $100 an hour for a welder to come up here and do a small thing for me, no one here wanted to, so that's out. Not gonna glue it back together either. I figure another 60-80k and it'll be time for a bottom end rebuild or dropping in an S&S

I did the top end rebuild on it twice. First time I found the prior owner had done something and it was running stupidly rich - to the point of about 4mm of carbon on the valves, and on the piston. I got another 20k out of it before it started blowing oil by again. Tore it down again, visited couple shops - cylinders slipped and pistons were toast, replaced it with S&S cylinders, Wiseco 10:1s, pair of refreshed stock heads, fueling lifters, S&S quickee rods, roller rockers, EV13 cam, and I was running a 2:1 exhaust (soon to be true duals). Got an S&S filter and intake kit, put a CVPerformance kit in the carb, and tuned it to run E85 since it is plentiful in my area.
Converted it to hydraulic clutch recently too - much recommend.

Current commutes to Denver are usually 80-85mph for 60 miles in the AM and 80mph for 60 mi into a 30mph headwind on the way home. So now I'm just redoing all the seals on the left side of the bike (and two on the right), new belt (current one is at least 10yo), regreased the rear wheel bearings and new seals, and a 34t final drive pulley. When the enclosed dry belt drive goes in it'll be good to go for the rest of the summer.

 

I took a good look at my inner primary this morning and I don't think you can machine the inner primary.. There's just not enough meat there...

 

Anyone know what the TPI is on the rear wheel adjuster screws?

I bought the andrews 34tooth pulley - which says for each tooth you add in Final Drive Gear, subtract 0.125" from current rear wheel position.