Tuesday, June 21, 2011

Another distraction. VAX Interceptor discovered in a barn!

My barn. Some parts that I bought back around 1975 or so have been identified as the most important parts of a very rare model of Royal Enfield.

When I first heard about the 1960 Royal Enfield 700cc Interceptor, I attempted to argue with the guy who told me about them. Turns out they're real. Enfield was working on the Interceptor design, and built a few prototypes using a hot-rodded Constellation engine, and shipped them to the US in 1960, two years before the formal introduction of the 750 Interceptor.
According  to the wikipedia article about Interceptors they made 163 of them. Other sources put the number at 170 and 211. According to Burton Bike Bits Interceptor Registry there are only 9 (not counting this one) known to exist, either as complete bikes or as correctly numbered crankcases or frames. Mine would make 10.
I discovered what this was after I sent a list of engine numbers for crankcases that are in my possession to the REOC-UK to help them update a database they're compiling based on factory records vs what is known to exist now.
The  following is copies of part of an email exchange I had with the REOC president regarding the engine and frame numbers that I sent to him.

Hi Carl,

Thank you for the engine numbers.

We didn't have any of the YB numbers you gave, so that's another three added to the listing.
This unfortunately also means that I cannot date or verify your comlete machine as it is not in our records - will have to assume that it is an original pair for now.

The damaged cases with a VAX number are from a 700cc Interceptor despatched in April 1960.

Your Tomahawk is even more interesting as the frame number has nothing recorded against it in the ledgers. The machines either side have similar engine numbers to yours, however, so it is an original machine although it was probably despatched in 1957, possibly '58 but definitely not '59.

As we do not have this machine in the records, I would most grateful if you could take a picture of the complete bike and close ups of the frame / engine numbers and let me have them as email attachments.

Please let me have the numbers of the frames you have as well - I can let you know what they are (hopefully) and annotate our records that the bike has been broken up.


I was asked to send in any frame numbers that I had, which I did.

Graham, I've found three Enfield frames in my collection of parts that I
forgot that I had.

I think they're all 500 or 700 twin frames.

The numbers are 6828, 7651, and 11051.

The two lower numbered ones don't have the large plate-type head steady
lug welded to the main tube. 11051 does have one of these, plus holes
for the triangular aluminum block behind the gearbox. It has an older
style swingarm with bronze bushings and grease fittings.

I hope this is of help in completing your records. Two of these frames,
6828 and 11051 are still usable, 7651 was "re-engineered" by some
shade-tree mechanic who thought an Enfield frame would work better as a
full-cradle frame. I'm afraid that if one was to cut off the crude lump
of pipe that was welded to the downtube, it would weaken the downtube
enough that it wouldn't be safe to use the frame.

I'd love to hear what model/year these frames are from.


The reply.

Hello Carl,

Thank you for the numbers.

7651 is a December '58 Apache (Brockhouse).

6828 could be either a May '58 Apache (Brockhouse) or a July '63 500 Sports
Twin (Shores).
I don't know enough about these to verify which one, even with a photo of

11051 is an April '60 700cc Interceptor, often referred to as the "VAX"
model, this being the engine prefix.
All these engines had 60xxx numbers, but the damaged cases you have are not
from the engine originally fitted to this frame.



After realizing that I had some potentially valuable parts, I dragged them out into the light, and realized that I'd misread the frame number, so I sent an email with the updated number.

Graham, I've got several people who are very interested in that vax
interceptor frame, so I got it out of storage to take some pictures, and
discovered that I'd misread the number.
It's 11059, not 11051.
Is this outside of the range for a VAX Interceptor?



Confirmed that I had an engine and frame which came from the same bike.

Hi Carl,

Assumption correct - your "corrected" frame number 11059 was indeed shipped
with engine VAX 60219 fitted during April 1960.



Then I got to thinking about the number stamped on the front of the same engine. I'd been told that this number represented the number stamped on the gearbox that was originally shipped with the engine as parts of the same bike.
Once again, I discover that I had a serial numbered part that came from this same rare Royal Enfield.
Another piece of the puzzle dropped into place when I remembered that I had one crankcase with no number stamped on it. This was among the parts in the purchase I made which included the VAX Interceptor. It's believed that Enfield shipped un-numbered crankcases to their dealers to install when an engine wasn't found to be repairable. They were probably expected to stamp it with the number from the original engine. This crankcase was probably the replacement for the one that was broken by a thrown connecting rod. Why the original owner bothered to keep the broken one, I don't know, but it was a good decision.
Here are pictures of the parts I have to build a VAX interceptor. All the other parts can be obtained, either from newly manufactured parts, or used parts. I have most of the engine parts that are needed.
Now I need to decide if I want a third Royal Enfield project, or if I should pass this on to someone else.
I've recieved offers.

The frame:

The engine.

The gearbox.

The replacement engine:


There's one more email I should copy. The REOC president said he found the factory record for my Tomahawk. It had been mis-filed in the ledger for the 700cc bikes.
Hi Carl,

I have just chanced upon the entry for your Tomahawk in the factory ledgers.
Some fool wrote it up in the 700cc book, so I have transferred it into the correct 500cc file on my spreadsheets.

It left Redditch on 28th November 1957 for the Brockhouse depot in the UK, then on to USA.



Monday, June 20, 2011

Buchanan's Spoke and Rim.

Nice people to do business with.

I called them up last week, and ordered a set of stainless steel spokes for the rear wheel on my Interceptor.

They don't stock spokes for Enfield wheels, but they'll make a set for anyone who wants one.
As long as it's for an Interceptor. They don't have specifications for spokes to fit any other model of Enfield. (until now; if you have an Enfield with 19 inch wheels at both ends, and 6 inch brakes)

I had to send them two of the old spokes from my Tomahawk so they could duplicate them.

The Tomahawk has 19 inch wheels front and rear, and 6 inch brakes front and rear, so both wheels take the same spokes.
Got the Interceptor spokes in a few days ago, and they're making the spokes for the Tomahawk as I type this. Time to start cleaning up some hubs. (the  rims have been ready since February)

Another bit of progress I've made is that I got the Tomahawk's crankshaft out. I'll take some pictures. There's some nasty, but repairable damage to the inside of the drive side crankcase caused by a thrown  rod, which wasn't fixed when the  rod was replaced.
Check back, I'll add the pictures to this post when I have them.
I don't know how some guys ever get any work done, stopping to take a picture every 10 minutes.  I prefer to work first, take pictures later.

Pictures of the damaged crankcase.
First, the washer on the timing side that the end of the crankshaft was rubbing on.
Just a sideshow. Here's the important stuff.
The broken area near the cam tunnel on the right side crankcase half.
This is a view from inside the crankcase looking up into the hole where the cylinder spigot goes.
Another view, this time from the top/rear of the case looking down into the cylinder spigot hole. There's supposed to be a hole there, just not quite as big and jagged as this.
And some marks on the inside of the crankcase where bits of metal bounced around. 
The oil return baffle. There are two screws missing, and it's bent. 
And here's the crankshaft with rods. One dirty, old looking rod, one shiny new looking rod.
  So that's it. Needs new bearings, and some welding. The rod bearings feel ok. I'm not even going to take those off.

Friday, June 17, 2011

Time's awastin'

I've got less than a year to go here. Gotta get to work.

Ok, here's what I've done recently (no pictures!)

The Suzuki forks are awaiting my friend's lathe to have threads cut in the top of the stanchions so they can screw into the Enfield fork crown. He's also going to cut a groove in the tops of the sliders to accept a standard Triumph style rubber fork gaiter.

I've started work on the Tomahawk engine. It has perfect looking top-end, cylinder bores, pistons, valves don't like like they need to be reworked.
The bottom end is a different story. It made an awful grinding sound when being turned over by hand, and felt very rough. I assumed the main bearings were breaking up.
What I found after partial disassembly (the drive side bearing is holding onto the crankshaft very tenaciously, and I'm looking for a suitable puller) is that the crankshaft wasn't quite installed correctly. It's supposed to be held in place on the drive side bearing using a spacer on the inside of the bearing race, and the engine sprocket and nut to pull the entire assembly tight. This establishes a certain amount of clearance on the timing end of the crankshaft.
Whoever put it together (I assumed, given the apparent low milage of the engine, that it was a "friday afternoon" factory assembly job) didn't pull the crankshaft tight against the drive side bearing, and the other end of the crankshaft was rubbing against a large sheet metal washer that's installed in the timing half of the crankcase to cover the bearing and end of the crankshaft.
Further inspection revealed that at some time, the engine had suffered a broken connecting rod. The case wasn't broken in the typical manner, so it didn't show up as a big hole in the front of the crankcase.
It did cause internal damage to the exhaust cam tunnel in the right side of the crankcase, and someone replaced the broken rod. This explained why the rod on one side was dark from age, and the rod on the side where I found the damage was still white aluminum.
The cam lobe on that side was rubbing the damaged metal which was pushed into the cam tunnel. Putting it together without fixing this damage was a mistake, because the damaged area was bad enough to allow oil to pour out of the cam tunnel, which is supposed to have a certain amount of oil in it at all times to lubricate the cam. I see no serious wear on the cam, either because there's still enough oil in there to keep that cam wet, or (more likely) because after reassembling the engine, they only started it up briefly, then shut it down and never ran it again. There wasn't much wear on the parts that were rubbing inside.
So once I've got the crankshaft out of the drive side case, I'll need to get some aluminum welding done to restore the cam tunnel. Didn't expect to have to be doing something like that!
I'll update this post with pictures after I've finished the disassembly.

I've also ordered some spokes for the wheels from Buchanan's.
They don't normally stock Royal Enfield spokes, so they had to make them up special.
They keep spoke specifications in a database, but the only Enfield spokes they listed were for the Interceptor. I ordered, and recieved a set of spokes for the rear wheel on the Interceptor. I also ordered a nifty spoke wrench which has one end that will work with most British wheels, and the other end will work with BMW slash-2 wheels. Its listed as the 210250 spoke wrench. That's because one end of it is 0.210" and the other end is 0.250".
I also sent them two spokes from the Tomahawk, which has 19 inch wheels with 6 inch brake hubs at both ends, so the spokes are the same. So if anyone needs replacement spokes for an Enfield with a 19 inch rear wheel, or a 19 inch front wheel with the 6 inch brake, they'll be able to make you a set.

Some progress. Not much but at least I'm moving on it.

Reply to Montoya's several comments.

When I first read your comments, I was a bit put off by your tone. You come across like one of those Concours afficianados who won't even put oil or gas in their trailer queens for fear they'll hurt the resale value or points scoring ability of their bikes. I plan to ride both of these when they're done, so "correctness" as determined by concourse judges or auctioneers is just not a concern for me.

But since you took the time and effort to compile your critique and suggestions (appreciated despite our difference in opinions), I feel that you deserve a reply, and since this is my blog, it seems easiest to reply in a new post, rather than cluttering up the comments section with more comments.

I'm not a purist, and never have been.  Both of these bikes were acquired by me with missing and incorrect parts on them, the Interceptor particularly so.  I originally put them together the way I wanted to, with limitations due to lack of knowledge at the time, serious lack of availability of parts, and lack of personal wealth.
I bought both of them back when very few people had any good information about them, and parts were almost impossible to obtain. They also both suffered from the typical period "modifications" of previous owners, removing front fenders, hacksawing back fenders, throwing "unnecessary" parts away.
The Interceptor was wrecked at least twice before I got it, and it had a set of Triumph forks installed (very, very badly).

I bought the Interceptor in 1972 (hard to believe it got to the state it was in after only 6 years), as a pile of parts. I was friends with the current owner, who took it apart to restore it.  It had the Triumph forks on it when he bought it, no front fender, a standard Dunlop rear fender with homemade stays, a Bates solo saddle, and numerous other aftermarket parts.  At the time, I was just a young kid who wanted the biggest bike I could get for the least amount of money. I simply put it back together with the parts I was provided with, and rode it around for several years like that.
Replacing all the missing parts wasn't an option at the time, although in hindsight, I probably could have. Since that time, I've purchased several stashes of old R-E parts, although tinware has always been very uncommon in such parts stashes.

The Tomahawk was purchased around 1982 from the original Indian dealer who had sold it new. I had no idea what it was supposed to look like at the time. It had no front fender, a chopped back fender, JC Whitney mufflers... It did have the original gas tank, front forks, engine, gearbox, toolbox and seat (not on it in the picture in this blog). When I put it together, I purchased a front fender from a Domi-Racer sale catalog that was listed as for an Indian Enfield, and given the low price (plus at the time, not knowing what the original front fender should have been) I snapped it up.
The toolbox on the bike is actually from my 1966 Interceptor, the original Tomahawk toolbox had been modified by a previous owner, who drilled four large holes in each side cover, and at the time, I didn't know if they could be fixed, so I just used the Interceptor toolbox. I've since then, gotten the holes repaired, and plan to use the original toolbox during this project.
For the record, this is one Tomahawk that does have all matching numbers, confirmed by the REOC-UK who has the original factory records. The frame, engine and gearbox all match for a Tomahawk that was shipped to the US in November, 1957 .
As for the nuts and bolts vs "resale value", like I said before, I don't care about resale value, I'm not in this for the money. As anyone who's ever restored a motorcycle knows, you're not going to make your money back on a restoration project, so you're a fool if you worry about things like resale value. I've restored other British motorcycles using SAE stainless fasteners altered to look like the original Whitworth or BSF fasteners, and nobody's yet gone over my bikes with a thread guage to determine if the fasteners are "correct" or not.
If/when these bikes are passed on to another owner, replacing the nuts and bolts, should the new owner care about that kind of thing, won't be difficult to do.

Regarding the Suzuki front forks, I'm putting them on for no other reason than because I want to. If you look at the picture I photoshopped, you'll note that I show an Enfield "casquette" headlamp/fork crown on it. I'm having a machinist friend modify the Suzuki forks to fit the Enfield part (which I purchased new from an Enfield dealer a couple of years ago). It's a "because it's there" kind of thing (and I have a really cool mod for the brake calipers which I'm not going to reveal until I've got the forks ready to install), plus, no matter how bad the Suzuki forks/brakes are compared with modern Japanese forks and brakes, they've got to be better than original Enfield parts, this is a cafe racer build, after all not a restoration. The only parts which will be irretrievably altered are a pair of old Suzuki fork legs. (now I'm going to recieve the wrath of Suzuki GT 750 fans!)
I am not planning on throwing the original Enfield forks away, and putting them back on the bike would take maybe a couple of hours of work if I decide I don't like the Suzuki forks.

Given the purpose of this project; to have two complete, presentable bikes for display at a motorcycle show which features Royal Enfield, I'm going to be making compromises, up to and including putting the Tomahawk back together with all the incorrect tinware if money and time prevents obtaining original parts.
I'm going to aim for having it completed with correct tinware if possible, but if I can't, as time and money permits,  I can continue to acquire more appropriate parts for the Tomahawk and return it to original specification.
My point here being that no future owners of either of these bikes will be cursing me for putting them together the way I did.  No changes to the original bikes are being performed which can't be easily changed back to original specification, and all the unused original parts which I currently have are going to be kept with each bike if I pass either one on to someone else.

Since my most recent post was a distraction, I guess I should conclude this one with an update to that distraction.
I've finally had a chance to use those cheap tires for what they were intended. (concours purists, you may want to close this page now to avoid damage to your sensibilities!)
I can report that they perform amazingly well on both pavement and dirt. Two of my friends who also own vintage BMW's bought pairs of these for their own bikes and we took a trip in Eastern Oregon which consisted of 50+ miles of somtimes very rudimentary dirt road, including two stream crossings, and the tires worked beautifully. These are by far, the best tires I've ever had on my R69S.

For anyone who's interested, these are Shinko 244 "Golden Boy" tires (made in Korea) in 3.50x18 size, and these old beemers handle both on and off road like these tires were made for them.
I may even put a pair on my Tomahawk, should I be able to restore it to original configuration within my timeframe. From looking at pictures of original Tomahawks, I get the impression that they were intended for light offroad use.