Crankcase repair (53 Vincent restoration)

Re: Crankcase repair

I will be mounting a Bob Newby belt primary drive so the primary cover need machining. I didn't want to machine and waste the original primary drive with matching mating number so I bought a new one. I do not have a milling machine so went for the DIY way; drilling 86 holes and used a chisel and hammer. Took me 20-25 minutes. Of course not the niceest look but I will grind the roughness down. It will not even been seen once the clutch cover is on.

Re: Crankcase repair



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While preparing the drilling and tapping of the welded up boss in the primary case half for the cover screw just in front of the chain tensioner blade adjuster I discovered the new hole would be too close to the edge. When the crank cases where damaged way back this section of the drive side was slightly deformed. Had to go back to the welder once again. I've lost count of how many times I've been there. While going there I also brought the timing side half as the timing cover and the crank case half were not fully mating each other on the front side just above the oil filter chamber. Then some more filing and sanding. Now it is good enough.

Re: Crankcase repair

Got the cylinder heads back from Germany a week ago. Now with new valve seat inserts, valve guides and valves.

Re: Crankcase repair

About two weeks ago I heated the timing side crank case in the new barbecue and assembled the oil pump sleeve, ... and forgot to put the outer roller bearing race in first. :evil: What the #$@&%*!
Had to pull it out again. Did it the right way now during the weekend.





Now finally correct!

Re: Crankcase repair

As I wanted to replace the standard camplate spindle with the Neville Higgins' version I had to bore and tap the crank case a bit deeper. Took a while to get it set up properly in my pillar drill. As the lower section of the original hole is wider I made a sleeve out of one of the old brass valve guides.

Re: Crankcase repair

During the second last visit to the welder he added some material around the edge of the camplate spindle thread and on one of the cylinder heads.

Re: Crankcase repair

Hey Patrik,

Have you painted the cases yet? I'm interested to know how that works out.

Bob Newby belt drive... hmmm...

I had that set up on 1330 motor and had a lot of problems. I put it down to the fact that the double sided belt doesn't work well in this setting.

My hypothesis is that the Vincent cases are such big chunks of metal that expansion and contractions means that when hot, the clutch drum and alternator pulleys 'drift part' thereby causing the teeth to partically dissengae, thus putting stress on the teeth. If set too tight, the pulleys can effectively 'crush' the belt. Either way isn't good!

Patrick Godet told me he has quite a few Newby belt drive associated parts on the shelf that he won't use as he won't fit one to a road twin again after the debacle he had with mine! So if you really want to go down that route, it may be worth giving him a bell, he might be glad to sell you some stuff cheap.

Re: Crankcase repair

Once again, no surprise I guess, I did not manage to get all the parts together for the Scandinavian Rally. At least this time the crank is assembled and the cases bolted up. I realized on Monday earlier this week that getting the engine ready would not be feasible. Some days everything works out fine and then suddenly you get stuck on some small issue for hour after hour.
Right now I'm putting the gearbox together. Tested yesterday evening but wasn't sure I got it right. Woke up early this morning and scrutinized Vincent Motorcycles by Paul Richardson's, Riders Handbook, Know Thy Beast, the Workshop Instructions Sheets and of course the new and old Parts Book (Vincent Parts Drawings (MO...) and Alternative Parts Book). I now think I know exactly how the camplate should be located when engaging the ratchet shaft bevel. There is no "1" stamped on my camplate as described in the Workshop Instructions Sheets but now I know were it is.

Fast Eddie, I have not painted the engine yet. First I thought about doing that before putting the case halves together (I guess that is what most people do) but I decided to instead mask and paint the engine once all covers (except kickstart cover) and the cylinder heads are bolted on. Maybe a strange decision. One reason for this decision was that I thought omitting the paint job would giver me a bit more time to get the engine ready for the upcoming weekend. Now when that is not going to happen I still do not want to split the cases again. Hopefully not for a long, long time.

One big reason for giving up this time was when I realized that the Bob Newby clutch+sprocket did not fit at all inside the cover even though I have removed the section that normally sits between the clutch and primary chain sprocket. I apparently need to remove more alu from the primary cover and possibly still need to fabricate a distance piece like Worntorn did. Which I of some reason did not get.

Some pictures since last update will follow.

Re: Crankcase repair

Using a sheet of glass with glued on emery paper (180 grit) to plane the partitions:


Before:


After:


Did the same procedure on the muffs, cylinder heads and covers. Now could see some markings I hadn't noticed before:


Similar on the partition surface of the case halves:


This one inside the case I've seen before though:


The machined primary cover seen from the inside:


Increased the oil hole between the crank and oil pump worm to 5mm as suggested (don't remember who right now):


In order to get the ends of the timing spindles on level I made up a temporary tool using a magnetic carpenter's level. Purchased a set of neodymium magnets and used a metal ruler and 4 of the shims I acquired for the crank shaft bearing distance pieces to get the right height:






The outer distance piece (just before assembling the outer race of the second conical roller bearing) consisting of two 3mm washers and three 0.5mm shims. This was needed in my case to later get the conrods centered in the pistons/cylinders:


Ratchet shaft bevel and bearings with lock screws and applied Loctite:


Just before the case goes together:


Finally bolted up. At last


Old clutch shaft and new before assembly of Constant Mesh Pinion G6:


Location of "1" as described in the Workshop Instructions Sheets:


Maybe I will fit the geabox internals after work today, but tomorrow I will head south to Västervik to join the Scandinavian Vincent Rally 2017. Going by car again
Hope to get some more inspiration to get the bike rideable this summer. But will for sure envy the others on their Vincents.

Re: Crankcase repair

I just came back from the Scandinavian Vincent Club Rally. I brought the engine with me in the car and had great discussions with several members. Ernst Hegeler, a German who owns a genuine Black Lightning, makes new crank cases and covers and have built a few engines with electric starter with the starter motor located where the dynamo normally sits, told me that I need to machine the inside of the cover as much as possible to make room for both clutch and belt. If I don't do that my 30mm belt won't fit under the standard primary cover even if I put the sprockets as far in as possible, unless I make a 8mm spacer between the crank case and cover. I might still need to make a thin spacer.
Another member who had managed to fit a Newby belt under a standard cover some years ago also machined the inside of the cover but before that he had the cover welded on the outside to add material. This is according to him a must to avoid using a spacer all together as there is not enough material to machine away on the inside to make room for the belt, without breaking through the wall of the cover in front of the clutch on the upper and lower side.
I was also told that when putting the clutch as far in as possible the clutch shaft will need to be shorten. I saw that Worntorn did that as well on his 1360 engine.

Last evening I measured as good as I could how much I can machine away on the cover and concluded that I will need to add some material on the outside of the cover to avoid adding a spacer. During the rally one of the club mates kickstart crank broke while we tried to start his Black Shadow he had brought on a trailer. His bike has been resting since the eighties and he just had his magneto serviced but it did not work properly so we convinced him to buy a new BTH (he just now ordered one). Anyhow I brought the crank with me home from the rally to have my welder fix it and I just passed by this morning on the way to work bringing both the kickstart crank and my primary cover. Hopefully I can pick up the parts next week.

All the best / Patrik

Re: Crankcase repair

Very meticulous and methodical work; well done.

Re: Crankcase repair

Thanks GP, I hope to ride the bike for many years without another renovation so I prefer to do it as good as I can this time.
I'm now in contact with Bob Newby about ways to move the belt inwards as much as possible. Also investigating possibilities to extend the length of the splines of the clutch shaft approx. 6 mm. Grinding the hardened shaft might work.
Keep you posted / Patrik

Re: Crankcase repair

Buellingvincent said:

Thanks GP, I hope to ride the bike for many years without another renovation so I prefer to do it as good as I can this time.
I'm now in contact with Bob Newby about ways to move the belt inwards as much as possible. Also investigating possibilities to extend the length of the splines of the clutch shaft approx. 6 mm. Grinding the hardened shaft might work.
Keep you posted / Patrik

Click to expand...

Patrik, if I were looking to build a road going Vincent twin that was gonna give high mileage, long service, minimal maintenance and top reliability... I'd be fitting a primary chain...!

And I'm a huge fan of belt primary drives...

Re: Crankcase repair

Patrik,

You might ask L.A.B. or Jerry to re-name this thread "53 Vincent restoration" or something along those lines, as a casual viewer may never know what an excellent thread this is sure to end up being. At first glance, I myself thought, "great, a thread about welding some cracks"...

Re: Crankcase repair

Fast Eddie,
Yes you are most probably totally right that the original chain primary is the long life solution. Now once I got into this belt drive idea I have to do it. Maybe just for the sake of doing it. :twisted:
Most important is that I do not want to split the cases for a long, long time. Fitting a new belt once and a while is fine.

Grandpaul, Thanks!
Well the focus from the beginning was the welding so the name came from there. I did not expect it to be such a journey to fix the engine. Thought it was more like a bit of welding and then just assembly.
A new crank, conical roller bearings, a belt drive and repainting was not even in my wildest dreams on my list.

I have concluded that extending the splines on the clutch shaft is not an easy thing as it is hardened. From a strength point of view the spline length must by far be well enough for a 55 hp engine. The suggestions I've got is to turn a groove at the inner end of splines on the clutch shaft to be able to move the clutch further in. Or preferably shorten the splines of the clutch as this piece is not hardened. I think I go for the latter.

Re: Crankcase repair

There is always the option to properly cut the splines deeper then send the mainshaft in for a salt bath heat treatment / nitriding. Yes, it costs a bit, but it IS a viable solution.

Re: Crankcase repair

Yesterday a job colleague helped me shorten the spline section of the clutch hub in a lathe. About 4 mm shorter. Will probably need to enlarge the conical chamfer a bit more to really move the clutch as far inwards as possible over the shaft splines.

Before:


Opened:


After:


Have not tested on the shaft yet as I met up with some old friends last night for a few beers. Very nice but feeling a bit slow today.


One of the pictures is showing the loose balls bearing of the clutch. We didn’t want to remove the spindles and studs so we used the biggest lathe in our prototype shop and managed to clamp the chuck on the rim.

I also picked up my mates kickstart crank and the primary cover from the welder yesterday. Now I have some more alu on the outside so it should be possible to machine the inside enough (I hope) to fit it over the belt drive. Some filing, grinding job of the outside will hopefully make it look nice and almost as stock.

Photobucket has decided to demand Plus 500 subscription to allow 3rd Party Hosting so the picture links to Photobucket are cut. As the charge is $399.99/year I will stop using them ASAP.

I will look for another provider for all pictures previously shown in this thread.

Testing

https://goo.gl/photos/33ruKpRYv34pgCM49

Imgur seems to work ok for me, for now.