What is the best approach for restoring a Vincent?

Magnetoman

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I have a how-to question for those of you who have completely restored a Vincent before, about the best procedure to follow. My question isn't about which modifications to make, what paint to use, etc. (although, such questions could come later), but instead is at a more "global" level. To ask my question, I have to give some background information:

Although I show up on this forum as a 'guest', that's because I don't have my VOC member number yet since I just rejoined after having been a member through the 1990s. I have a workshop with full size lathe, mill, hydraulic press, TIG, bore gauges, micrometers, etc, and have completely restored other motorcycles before (ranging from a Bultaco to a Gold Star), so I'm not completely new to this. I also have copies of all the relevant Vincent books and manuals, and a nearly complete set of 'MPH' through c2000.

With the above as background, I'm now getting ready to start the complete restoration of a non-running 1950 Black Shadow that I've owned (in non-running condition) for many years. I will do this restoration over evenings and weekends so, even if I somehow manage to keep to a rather optimistic schedule, it will take at least a year. While it might be more "efficient" or cost effective if I could take the Vincent completely apart, ship all ~1000 fasteners in one batch to be replated while working on the engine, then put the motorcycle all back together, that clearly would end up in tears. I will need to break this restoration into "modules," each of which I can restore separately (before forgetting which spindle bush goes on which exhaust lifter) before moving on to the next module. My question is, what should those modules be for a Vincent?

The way standard British bikes are made naturally lend themselves to such a module-based restoration. The engine and cycle parts can be restored separately and remated only at the very end. It doesn't matter if the engine is restored first, or last. The frame serves as a base unit, with it sitting alone on the stand at the start of the restoration. The forks, wheels, tanks, engine, etc. each are independent "modules" that can be restored in just about any order and added to the frame at just about any point. However, a Vincent isn't built that way. So, given that I really do have to do this part time over an extended period, meaning that I will need to finish something before starting on the next, I'm hoping for some sage advice on the best order to use when attacking a Vincent.
 

riptragle1953

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Line bore the cases using the small bearing down for datum and bore to fit Al.Bz. sleeves at a 2.5 inter. fit.... and that's the start .... Phil Irving's book "Tuning for Speed" has a lot of this type of info.
 

Magnetoman

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Line bore the cases using the small bearing down for datum...
Thanks very much for your quick response. Although detailed information like this will be invaluable when I reach that point in the restoration, at this point I'm looking for suggestions on an overall approach to take.
 

riptragle1953

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Precision measuring and good machining ..... and the willingness to create special fixtures and jigs for you machine tools. Do read "Tuning for Speed".
 

Magnetoman

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Precision measuring and good machining ..... and the willingness to create special fixtures and jigs for you machine tools. Do read "Tuning for Speed".
I understand what you mean, and this is not an issue (I first read "Tuning for Speed" nearly 40 years ago). For me, precision machining, and the willingness to create special fixtures and jigs, are central to my enjoyment of doing work like this. As an example, rather than trusting my mill's DRO, I carefully calibrated it against a 2' Brown & Sharpe standard at 68oF. I then determined the DRO's differential thermal contraction, so that I could even machine a piece of Al as long as 20" at 100oF and have it fit a mating piece of stainless I machined at 68oF to within 0.0002" when they both came to equilibrium at, say, 81oF.

I will be in no hurry to rush through this restoration, and I'm paying myself $0/hr. to do it. So, spending, say, 6 hours making a special jig that only will be used once for an operation that might take just 15 minutes is not an issue.
 

timetraveller

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I will make a suggestion but it is not the only way to go and some of what you do has to be decided by your circumstances rather than your abilities. What I am going to suggest is not the way that I would do it but I have been playing with Vincents for 55 years (where did they go?) and can readily recognise most parts and where they fit. If this is your first attempt at a Vin then you have to be more organised than me. There are probably more subassemblies than at first seems to be the case. It is not just the front and rear ends and the engine/gearbox assembly. You will also end up with fuel tank, seat, wheels and probably items like the Shadow clock, footrests and hangers etc. It will also depend upon whether you want the bike to be standard or are prepared to incorporate modifications which have been shown to be useful over the last 65 years.
Before starting on the engine/gearbox assembly why not consider renovating some of the cycle parts first to get a feel for how Vincents went about things? The rear frame triangle or the wheels comes to mind as parts which can be worked on in isolation without ending up with bits of engine and gearbox spread around. Consider doing both wheels first. Certainly not the most exciting parts but they will have to be done and once restored do not take up too much space while the rest of the work is being done. If the job is going to take a ‘stretchy’ year then you might choose not to fit the tyres yet in case they start to deteriorate before the rest of the work is finished. With regard to the wheels; do you want to use the original brake plates or the currently available machined from solid brake plates which are much superior. Check the brake drums. If the bike has not seen much use before it was stripped they will probably be alright. If, on the other hand, they are well worn (possibly oversize) consider new brake drums as after 60 years some of the originals are starting to break. The rear frame triangle is also a relatively compact subassembly which can be stored away once finished. You can decide on what type of paint to use, whether you are going to use the original nuts and bolts and get them plated or go for stainless steel ones which are readily available now. Stainless mudguards or original aluminium ones? Your choice.
Once those decisions are made they will affect how you are going to treat the rest of the bike. Wheels and the rear frame are relatively straight forwards and should not cause too many problems. The front forks could be your next project. The adjustment of shims etc. there will be a steep learning curve and should lead you nicely to the engine/gearbox assembly. Although not often considered, stripping down an engine is one of the most important parts of a job. It is while doing this that one can see what has lasted, what has been bodged, what had come loose etc. Rip is right in that if the main bearing bores are knackered then line boring and then sleaving them is a good way to go but you might be lucky and they could be in good order with tight bearings. Check them first. If they are still in good order and you can fit standard replacement bearings then do peg the new bearings as well as shrinking them in. The standard set up, when new, could last a long time but many crankcases showed signs of the drive side inner main bearing ‘walking’ inwards when the bikes were only a few years old. My advice is peg them. You will find much conflicting advice on line and there is not only one way of making a good job but speaking only for myself I like to use modern low expansion pistons with low clearance, two start oil pumps, sealed valve guides and so on. These are all things that were not available 60 years ago and they do help to make the final job a pleasure to use. Good luck with the renovation.
 
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vibrac

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Here is my small contribution Vins are not like normal bikes you cant do the frame and pop the completed engine in
without jigs the critical path is [engine -front - back] rather than the conventional [frame -or- engine -put em together]
this is not a good way to go
I have found that its best to always have at least two paths to follow three is even better because always something out of your control will halt one build path
so a frame to hold the ufm so all the front end can be built and a spare vice or clamp so the rfm and rear can be built while the engine is in surgery is a better way
Having said that on my Flash I am trying a engine jig that is strong enough to hold the completed bike but in that case I started with a fairly good engine that just needed timing and primary and anyway as its from disparate parts with modifications its a build-strip- pretty up-rebuild job whereas a refurbishment is often a one pass operation
 

Bill Thomas

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Hello, I say engine first, That will take the most time and money, Then when you see it sitting on the bench you will want to get going with the rest, It's all in the Mind, !! Good Luck BIll.
 

Big Sid

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A solid motor stand that goes through the front sidestand pivot tube is worth gold during disassembly and reassembly . It's great for long time storage too when the rear stand is deployed , ie both tyres off the floor .
We had some built and the first batch is gone but if there is more interest we can make more . It's solid as a rock , won't tip over .
Let us know if desiring one . sid@bigsid.com .
 

Magnetoman

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Hello, I say engine first, That will take the most time and money, Then when you see it sitting on the bench you will want to get going with the rest, It's all in the Mind,
Actually, I am most looking forward to doing the engine, so I am hoping to do it last, to provide a carrot to keep the rest moving along.


the critical path is [engine -front - back…
This suggests the engine should come first.


I have found that its best to always have at least two paths to follow three is even better because always something out of your control will halt one build path…
I agree with this. My one-module-at-a-time is an idealized path for me to strive for, although reality always adds complexities. As you say, if one rigidly sticks to a single path it will mean waiting months at various times until backordered $5 parts are delivered. Still, modularizing a build allows one to give up on a given module, set it entirely aside, and switch to another module. Working on two simultaneously always has the danger of bits from one section of a bike confusingly appearing in a pile of parts for another section.


…so a frame to hold the ufm so all the front end can be built … am trying a engine jig that is strong enough to hold the completed bike …
My Vincent rebuild hasn't been months or years in the planning, but actual decades. During that time I've fabricated all the jigs and special tools mentioned in MPH and other sources in the years up to ~2000. One of the jigs I made, that I didn't see in MPH, converts an engine stand (750 lb. capacity) into a Vincent stand. The UFM attaches to it and, in principle, allows it and the engine to be rotated through 360-deg. (not enough swing to do this with the wheels attached).


If this is your first attempt at a Vin then you have to be more organised than me.
Yes it is, so yes I will have to be. Much good advice is interspersed in your post, and I will take it all to heart. As for an overall procedure I extracted the following:


--Consider doing both wheels first.

-- The rear frame triangle or the wheels comes to mind as parts which can be worked on in isolation without ending up with bits of engine and gearbox spread around.

-- The front forks could be your next project.

-- should lead you nicely to the engine/gearbox assembly.

Does this procedure seem reasonable to others? Also, you suggest doing the engine last (which is what I hoped to do), but Bill Thomas and Vibrac suggest doing it first (but, for different reasons). Comments on this?
 
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