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Posted By: redmosquito1 Bottom end rebuild! - 03/24/20 8:35 pm
Recently sold my Harley so until I get the '67 BSA A65L running I'm without a bike. I'm home avoiding the virus this week and next I figured it was a great time to split some cases!!!!

I got the cases apart, went much easier than I expected and thankfully didn't find as much damage as I thought. I do know this is not the first and likely not the second time this motor has been apart, the rod journals are .020" under sized which makes me think they've been ground at least twice. I have mismatched piston rods, one is smooth and shiny and one is shot peened, but they both weigh the same so thats a positive. The oil pump drive gear lock nut was destroyed, it was spinning loose but needed to be pried off to remove it and thankfully the threads werent messed up, the drive sprocket nut fell off in my hand once I got the cover plate out of the primary case. The main damage was caused from missing crank shims. I guess the previous builder forgot to check crank end play and install shims but you can def see the damage on the roller bearing. The outer race managed to crack and was wearing down were it split. I'm pretty shocked the motor didnt grenade in my very short running of it.

All in all the crank bearing surfaces look really good, how do I know if I need to have them reground or polished? I was thinking I could just order up new bearings and run it like that?

Any tips on removing the sludge trap tube with out a tap or similar sized bolt? I am going to replace it, mostly because I tried tapping it out from the little hole opposite the plug but that doesnt seem to move it. I can't go get a bolt/tap now since MI is on lock down.

I did get the timing side bush and outer race of the main bearing out of the case halve and the halves look good. I'll have more questions as I go so I'll post them here to keep everything organized.
Posted By: DMadigan Re: Bottom end rebuild! - 03/25/20 12:44 am
I think you should get a manual first. Try CBS above.
There is no hole opposite the sludge trap plug, maybe a countersink hole for grinding the rod journal. The bolt going through the flywheel holds the sludge trap, take that out first. A large EZ-out or tap can be used to grab the tube and pull it. Sometimes a hooked rod can be used to catch the bolt hole from the inside.
Use a micrometer on the rod journals and main to see if they are 1- within diameter tolerance, 2- tapered, 3- round.
You should have left the main bush in the case until you measured the bore and main diameter.
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/25/20 1:11 am
I've got a manual and parts book and the like. I've had the bike for a while just never went into the bottom end before, but now I'm glad I did. Hmm, that would make sense as to why the trap wasn't moving. I guess I'll have to wait until I can pick up a easy out or tap, hopefully this virus wraps up quickly but I feel like it wont.

Why should I have left the main bush in? If I plan to replace it won't I have to align bore it to proper clearance? or are you saying incase it was still usable?
Posted By: TR6Ray Re: Bottom end rebuild! - 03/25/20 1:30 am
Running a 5/8-11 tap (with a nut and washer threaded onto it) into the sludge tube is the easiest way to pull the tube. If you don't have that size tap, you can make a puller from an old bolt or a piece of threaded rod and a 1/4" grub screw, as invented by John Healy. That's what I used. CLICK
Posted By: Beach Re: Bottom end rebuild! - 03/25/20 1:59 am
Originally Posted by redmosquito1
I've got a manual and parts book and the like. I've had the bike for a while just never went into the bottom end before, but now I'm glad I did. Hmm, that would make sense as to why the trap wasn't moving. I guess I'll have to wait until I can pick up a easy out or tap, hopefully this virus wraps up quickly but I feel like it wont.

Why should I have left the main bush in? If I plan to replace it won't I have to align bore it to proper clearance? or are you saying incase it was still usable?
Buy a tap from amazon and have it delivered
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/25/20 2:01 am
Thanks TR6 that make a lot of sense, going to go give that a try in a little bit.
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/26/20 9:53 pm
Finally got the sludge trap out. Ordered a tap which will be here Saturday, but went out and tried to pull it using a bent piece of metal. A little work and she popped right out. It was surprising that it was not fully caked with sludge, although it had its fair share of gunk, there are 2 punch marks so it’s been cleaned at least once.

I took some measurements of the crank journals, timing bush journal measures 1.497”, both rod journals measure 1.666”. The con rod bearing not torqued measure 1.672 and 1.676. Leads me to believe that at some point a con rod broke and the journals were ground. Then they left the spacers out and cracked the bearing race on the primary side.

All journals seem smooth but I’m thinking it would be prudent to get them all reground, polished and balanced.

Is switching to a main primary side ball bearing a worthwhile venture? I know you lose a little side load capabilities but my understanding is you then don’t have to worry about crank end play as it’s pulled tight to the bearing race. Thoughts?
Posted By: leon bee Re: Bottom end rebuild! - 03/27/20 3:12 am
I usually go with the ball bearing, but not to deal with those end play issues. It's just cheaper, and I don't ride like a maniac anymore, try to take it a little easy on the machinery. I do try to buy a good bearing, some brand with a good reputation.
Posted By: NickL Re: Bottom end rebuild! - 03/27/20 3:24 am
Just make sure the crank is central.
If the timing side thrust washer comes adrift it will cause damage. Centring the crank should
prevent that from occurring.
The ball race is fine, just doesn't last as long if you cane the living daylights out of it.
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/27/20 8:14 pm
So if I switch to the ball bearing should I order the earlier shims or go with the later style shims?
Posted By: Allan G Re: Bottom end rebuild! - 03/27/20 8:37 pm
Go with the shins that suit your year of crank. The bearing won’t make any difference in this matter
Posted By: Mr Mike Re: Bottom end rebuild! - 03/27/20 9:37 pm
I converted my 66 lightning to a ball bearing many years ago. Rode it for about 4-5 years afterwards and sold it to Richard who still owns it I believe. The ball gives up some load carrying capacity but keeps the crank from shucking back and forth. Make there is a tad of clearance so when you tighten the case screw it doesn't side load the ball. I put the TS thrust washer back in but you can likely leave it out. The details area bit foggy for me after all these years but I think that is how it works. Someone correct me if I am missing something.

Mr Mke
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/28/20 10:36 pm
How important is the chain Oiler? The primary cover screw hole boss was cracked and no longer allowing a screw to tighten. However I could remove the chain Oiler and run a longer screw with thread sealant to tighten the cover, losing the chain Oiler.
Posted By: Mark Z Re: Bottom end rebuild! - 03/28/20 11:43 pm
Not important at all. I'm thinking that maybe in the sixties, products like PJ-1 and Chainwax (which work much better than motor oil as chain lubes) were not readily available.
Posted By: BSA_WM20 Re: Bottom end rebuild! - 03/29/20 8:51 am
Originally Posted by redmosquito1
How important is the chain Oiler? The primary cover screw hole boss was cracked and no longer allowing a screw to tighten. However I could remove the chain Oiler and run a longer screw with thread sealant to tighten the cover, losing the chain Oiler.

Not a good idea because it is also a breather for the primary .
There are drilled inspection caps or put a tube on the outlet and run it up to the oil tank or some where out of the way
Posted By: Mr Mike Re: Bottom end rebuild! - 03/29/20 1:34 pm
I am with Mark on this one. I use the PJ-1 and have plugged all my bikes with that chain oiler system. One less drip on the shop floor. The hole is really pretty small for any effective breathing. In their last year BSA put more effective breathing on the B50 by adding a half inch hose and drilling holes from the primary to the crankcase. I am not sure I agree with mixing engine and primary oil but modern bikes do it but they also have a good filtering system.

These old bikes are a lot of fun to chat about.

Mr Mike
Posted By: BSA_WM20 Re: Bottom end rebuild! - 03/30/20 4:01 am
Breather ws probably not the best word to use.
Vent would be better that will allow the water that has condensed in the chaincase because we only ride once in a blue moon now day to escape when the oil gets hot on one of the 3 days a year you ride far enough to et the primary oil hot enough.
Posted By: Mr Mike Re: Bottom end rebuild! - 03/30/20 2:02 pm
WM,
True enough. Back in the late sixties I rode my B25 as a daily commuter for a couple of years. I could almost go the week on 50 cents worth of gas at 27 cents a gallon for hi test. The B25 would ping terribly on regular. I didn't have any good riding gear in those days so the winters were tough on my 12 mile commute one way. The B25 held up pretty good for those two years. Today, my only remaining BSA gets out a couple times a year and some times for only a run around the block.
Mr Mike
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/31/20 2:30 am
So I'm about to order some parts and want to make sure I order the correct timing side bushing. My timing side journal measures 1.498", best I can tell the standard size bushing is 1.501". I would then assume I should order a .010" undersized bushing to allow for align honing and then to allow the bushing to be machined to the correct clearances of .001"-.0015", is that correct?
Posted By: Allan G Re: Bottom end rebuild! - 03/31/20 8:34 am
Yes. You can order any underside bush. But it’s only more work for the machinist. The machine at should grind the crank until it’s true (tell them to make sure it maintains the radius) then they will machine/ream the bush to match the crank.
Posted By: Mr Mike Re: Bottom end rebuild! - 03/31/20 12:45 pm
The best way to do this is to get the crank done first, Install an undersize bush in the case and align bore the bush to the proper clearance. BSA used to make bushes of various sizes because most of their dealerships did not have machining capabilities like align boring so they tried to have mix and match parts. Grind the crank to "X" and buy bush "Y". It is best to machine the final bore to the minimum acceptable clearance over the finished, polished crank.

Mr Mike
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/31/20 5:56 pm
Ok, I’ve decided to ship both case halves and crank up to E&V Engineering and just let them handle it. This way I figure he can install and set up the bearing and bushing and if there is any problems with the crank he can handle that as well. I kept going back and forth but at the end of they day I know it’ll be done right and I won’t have to find a local machinist that can do the work properly. I hope to get it boxed up and out by weeks end. We will see.
Posted By: Mr Mike Re: Bottom end rebuild! - 03/31/20 7:21 pm
I did mine at a local shop that I trusted but I have had Ed V do other work for me and it has all been top notch. He is up in your neck of the woods too. Shipping cost killed me from sending it to Ed.

Mr Mike
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/31/20 8:27 pm
Yeah I'm currently debating driving 5 hours round trip to drop the parts off or making a box and shipping it. Factoring in gas it wont cost me a bunch to ship them, maybe $10 more than driving, but it might be a worth while trip to check the place out. Although, with the virus running around I'm not to sure how keen they'll be letting a random stranger wander around their shop. For that matter I don't know how comfortable I'd be doing that.
Posted By: Mark Z Re: Bottom end rebuild! - 03/31/20 9:01 pm
Red, have you tried to ship anything in the last year or so? I think you may be in for a shock. Get an estimate before making your decision; I think you may find it will be significantly cheaper to drive there, even if you don't get to wander around the shop. And, there's the peace of mind in knowing that it will not get damaged in shipping.
Posted By: redmosquito1 Re: Bottom end rebuild! - 03/31/20 9:57 pm
Mark I haven’t checked other than using ups website. I’m leaning more towards driving it just to get out of the house for a few hours. Plus it’s a nice little cruise.
Posted By: redmosquito1 Re: Bottom end rebuild! - 04/01/20 2:40 am
Does anyone know of an engine case half bolt and stud kit? Looking over the case half bolts and a couple of bolts and one stud is necked down and the holes are cross threaded. I figure I'll need to at least helicoil 3 holes and need new bolts/studs for a few other ones. This motor was super hacked together and I'm still shocked it didn't go splodey in the short time I rode it.
Posted By: Allan G Re: Bottom end rebuild! - 04/01/20 6:45 am
As your giving the bottom end to Ed, ask him if he will sort this side for you, as you may or may not know he is a parts supplier as well as machinist, whilst he has your cases it will be worth while him doing the full job
Posted By: redmosquito1 Re: Bottom end rebuild! - 04/01/20 12:18 pm
Allan that’s my plan as far as having heli coils installed. British fasteners wants $70 for the correct 5/16-26 heli coil kit. I only need 3 holes repaired so Ed would have to charge me an insane amount to make it not worth it. As for the bolts and studs I didn’t think about him being able to source some. I’ll definitely ask when the parts get shipped/dropped off.
Posted By: Mr Mike Re: Bottom end rebuild! - 04/01/20 1:39 pm
Redmosquit,
I agree with your concerns regarding COVID-19. I rigorously support social distancing. If you drive, I would leave the box at the doorstep and speak to Ed from 20 feet or by phone. I talked to him often on the phone when he did work for me. I am sure he can correct your case studs. Sometimes replacing a stud with a thru bolt is a simple solution but Ed will know how to do all that. Shipping has not gone down over the past 20 years. It has steadily increased.
Mr Mike
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