So I'm halfway through an engine overhaul on a 66 BSA Spitfire. I had a mechanic split the cases for the bottom end) and diagnose what's going on and what he said to me is as follows:
1. Crank needs to be replaced and machined, or the one I have now needs to be machined, however it's almost as little as it can go (30 under, with a new timing bushing.
2. Some gears are missing teeth, replace 1-2 gears
3. Gasket set
Top end is worn, but doesn't need replacement. Pistons, rings, etc. are okay.
So I guess my questions are as follows:
1. The price for the crank, machining, bearing. He dialed a replacement crank in at around 200 dollars if he couldn't find a bearing that would fit mine, a bearing at roughly 80-100 bucks, and machining at 400.
2. If you can check the oil pump before reassembly to see if it is still good. I think it is, I've ran the bike before, but the crank had about 5 mm excessive play up and down, but when I was troubleshooting it oil was getting to the valves. Just don't wanna go through reassembling the bike, then having the oil pump needing to be replaced or something..or if you need to get to it if you can do it with the engine on the bike.
Joey, you will likely get both extremes in advice,...... but my $.02 is: The crank: Whats .030 under, the rod bearings? The timing side bush can be sourced in aftermarket smaller than was original allowed. I have had the steel bearing sleeve filled with a new brass insert, and machined to fit whatever the crank cleans up at. You don't need to go .010" increments. Even that said, Cranks are usually laying around cheap. I'd give you one that is able to be saved if you want to pay the freight CA - NY ! THAT is the problem with alot of things now. If you haven't taken the oil pump apart. DON"T Most do, and wish they had not. If it was working, flushing it clean and stop. I would recommend you try to replace the O-ring under the drive end snap ring if you can. Especially if your past experiece showed the motor would sump over a few weeks, Be very carful when mounting the pump. Alot goes wrong in what should be a simple step. Missing teeth !!! Where missing? I have not heard of timing gears missing teeth, so Trans? Even there is odd. Again, gears are not hard to find, but mismatched gears tend to run Noisey. Full face helmet. If you have been watching here, You know about the sludge trap issue by now I am sure. Here's a thought you might consider. Spitfires were built to make horse power, beat the Bonneville and sell BSAs. The motor is very stressed. You might want to lower the compression a bit. You will likely never feel the difference, motor will. Even if you plan to used the cylinder and rings as is (sounded that way), this can be done cheap. Sounds like you are deep into the reasons why some shy away from the BSA. It can be a bear, but you can win the battle. This board has always been a big help when the going gets rough. Good luck.
Thanks for your input KC. I may take you up on that offer on the crank, do you know the measurements on it? I'll discuss it with the guy doing my bottom end...
Definitely taking note on the O-Ring thing. I essentially got to ride the bike for approx. 5 hours before it started having issues that boiled down to the crank, so I don't know about the O-Ring under the drive, that just has to deal with sumping out the engine from the bottom, not the sludge trap correct?
I will also throw in what you said about the oil pump to him as well...I think it should be fine because oil was getting to the valves, and I rode the bike for hours straight with no issue, it seemed like all the issue was the play in the crank up and down (Approx. 5 MM).
Unsure on what gears as well. When you say "wear a full face helmet" is that for noise or safety? I wouldn't wanna have him mix up gears and have to worry about something locking up while riding.
I guess you are talking about Trans gears then. The mixing of gears is just a noise issue as they were no worn in together and make noise. I wouldn't worry about mixing gears causing a trans to "lock up". The "full Face helmet" was a wise ass remark regarding noise. Sometimes, you just have to ignore some of that stuff, but it can be hard to put out of your mind,...... so don't hear it! Oh, DO replace the trans output shaft bearing and seal if you have the Trans out. So simple, and such a pain later. That o-ring is just a seal on the small tach drive shaft coming out of the pump. It's not a concern for oil pressure loss IMHO, just one more on the list of possible sumping causes. If you aren't sure, sumping is when the oil in the oil tank drains down into the crankcase, and as it builds up enough level, is an issue. Sumping is just a PITA, not unlivable, but does get in way when you want to just kick and go. Just one more thing we love about these old BSAs. You still didn't mention where the crank is too small. I'll look at a couple cranks and see if I have a decent candidate. Some time back I tried to give away 3 A65 bottoms, this board and CL, ..... no takers. I really think you could find a lump like that closer to home, but whatever you want.
FYI for anyone else too, I guess for you too KC-what I am looking to find is a crank for a 1966 BSA A65, ideally with a bushing that's good, and in no needs of machining, with good big ends.
The gears I was referring to are the crank pinion and the idler gear. also...If there's a guarantee on the crank/bushing/etc. I would pay money, whatever anyone's just looking to get rid of I'll gladly look into but let me know either way just looking to get thing back on the road.
Try Ed V for a quote on an end feed conversion, this can save very badly worn cranks,, not last regrind big ends though.. It solves many an issue and from the quotes you have had probably would be about the same as getting a new crank, plus it will be a lot longer lasting as a repair.
Did you really ride it for 5 hours with teeth missing on the timing gears? or have they been replaced. Oil going to the valves is off the return side of the pump, with that much wear in the timing side bush, 5 mm!, not 0.001 ", you will have no big end oil pressure even if the pump is OK. The next thing is catastrophic failure of the LHS big end as it runs dry, seizing , snapping the rod and ventilating the case. You can test a pump in situ, after removing the crank worm drive refit the puymp and spin it with some rubber tubing fitted to a drill, but with a worn TS bush it will be unable to generate any real pressure.. . A bit pointless, your motor is on its last legs and needs TLC.
71 Devimead A65 750 56 Norbsa 68 Longstroke A65 Cagiva Raptor 650 MZ TS 250 The poster formerly known as Pod
Well, that's a First !! Not to sure you know this yet, but you really can't buy a crank and matching bush (sized to proper clearance) as a set and install them. That would be WAY too easy. The problem comes as you put the case halves together, and tighten the bolts, at some point, the crank will bind up. This is not because of pinch, but is due to the alignment of the 2 bearings in the case. The only way to fit the bearing to the finished crank size, is to have the cases bolted together, and align bore/ream the timing side bush using the drive side bearing recess or race as the Concentric aligning point. This is why it's hard to find a shop to do it. Mounting the complete case in a machine to do the job can be a real challenge. You may be getting somewhat discouraged by my remarks. I wish some others would come on board here......
Thanks everyone. I'm having sixth street specials help me with the bottom end, just because I don't have the tools to do so on my own/time/want it to be done properly. Looking to definitely do the bottom end correct once, then be done with it. My plan was as follows:
-Find crank pinion and idle gears on eBay, should be cheap
-Ideally, find a crank with a timing bushing that's a good fit and has good big ends already then machine into cases ideally (what KC was talking about?)
-New gaskets to be safe
If that doesn't work, find a crank, timing bushing, and machine the crank and the bushing into the case. Regardless, a professional is doing the bottom end part for me, I'll be putting the rest of it together, and to the best of my knowledge it all should be good...just trying to take my time so I don't pay an arm and a leg for parts/machining.
Thanks again for the help, this forum has been very informative, I really appreciate the two cents and parts links, etc.
Joey, Crankshaft end bushings are available up to .050 thick. However you might just be better off finding a different crank shaft that is in better shape. Yours being .030 over most likely means the engine saw some serious ware. Ask your Machinist if they have the capabily to line bore/hone the plain bushing. This means they locate on the drive side of the cases before boring or honing the bushing. Its very import that this setup is done correctly so the crank roller bearing and bushing are in the same plane ( same line ) The other thing is the sludge trap needs to be cleaned. Good luck Richard
Rich, I was told with a .040 under bush, having the crank and bush machined properly and installing it correctly, I would get 30,000-35,000 miles out of that, which seems alright like enough for me...I actually found out some other interesting news today, I could grab a fully rebuilt bottom end for $850, garunteed by the shop for being good etc., they went through everything. So I guess I have the option of buying that for the cost, and putting my working top end on it, throwing in my EI to the new engine, and hooking it up and being ok. Just run into the problem of having a different VIN on my registration with the new cases...so it seems like my three options are:
1. Buy rebuilt bottom end and reassemble old top end on new bottom end. Part out/throw out/ burn and piss in the ashes of bottom end that let me down
2. Buy $100 0.040 under bushing machine my worn crank and bushing, buy idle crank and crank pinion separately.
3. Buy new crank and bush (same guy that has engine) where the crank and bush are already good, and have that pressed into the case, obtain gears, and move form there.
Degree of labor from my mechanic varies in all of them but I'm crunching out roughly no more than $1600 no matter what. On the low end could land around $1300. Will keep everyone updated with what winds up happening. Cheers.
Hi Joey, I assume you have been learning at a fast rate, and have likely come to the conclusion that you can simply use your existing crank. At any rate, I used this as an excuse to see if any of my loose ones have any life left. Found 4, 2 are junk IMHO, 2 are able to be reground and used. Nothing is simply ready as is. If you think you need one after weighing the options, let me know, they won't be blowing away with the dust,...... that's for sure!
Thanks KC, I have a guy in NJ selling me one with a timing bushing where neither need machining for $445 for both. If for some reason things get bad with that deal, or circumstances change I will contact you for one of these. My crank is in really poor shape, it could be reused, but it definitely needs machining and it would be really far under anyways. The timing side is pretty messed up on it
Yeah, well I guess the bearing is new and already machined to match the crank so it's good to go. However I just got off the phone with my mechanic, and I told him about the brand new bottom end...he seemed really happy with that and I'd save tons of money on labor, and just the chances of other things going wrong by having a newly rebuilt and garunteed bottom end for 850 that fits my top end.
However, another problem now arises (of course, right). My registration is to my vin on my case...this new engine would not have the same number, and my frame is a mismatch...how do I get that sorted out as legally as possible...or just fuck it right? Jail's for cops haha
What year is the " new" bottom end, what else comes with it?, cams and timing gears hopefully, better still if everything is there bar the top end.. post 70 cylinder studs are larger , wont fit your barrels. Generally , later is better, some stuff changes on the timing side but the drive side stays mostly the same.
Last edited by gavin eisler; 09/25/152:29 pm.
71 Devimead A65 750 56 Norbsa 68 Longstroke A65 Cagiva Raptor 650 MZ TS 250 The poster formerly known as Pod
Joey, I don't think you'll have any trouble registering your bike; NY is pretty lenient, especially with pre-1972, non-titled vehicles. You can register it by the frame number, just take a pencil rubbing of the number, and use the "lost registration" procedure, and say you were the previous owner. As long as that VIN was not registered by someone else in the last seven years, you're in.
WOW !! Registred here 9/3/15, and done and riding 10/21/15 !!! You work fast !! I could ues project advice from YOU !! Glad to hear you had success and are on the street enjoying the results of your efforts. Good deal! Please pass on any items of rebuilt interest you have learned, including who you settled on to do the machine work. Oh,..... any chance of some photos? We love'em here, even if a PITA to post..........
Thank you. Well it couldn't have happened without everyone's advice on this forum as well. I bought the bike "ready to ride", and essentially 3 hours found it was nothing like that. After the cases were split, I found that it was the bottom end that needed everything and I got super lucky with this part. I found a bottom end to a 66 spitfire rebuilt 15 years ago ready to go. So the top end went back on and she was good. All that had to happen was priming the oil pump, because it was a little dry after sitting on shelf for 15 years haha. But the guys from Sixth Street Specials did a great deal of help, and so did Classic Cycles in New Jersey, I purchased the bottom end from them. And of course, this whole thing was a learning experience. I'll put a picture up.
Photos of completed bike:http://s578.photobucket.com/user/jyedowitz/library/?sort=3&page=1