I've taken a little bit of flack lately concerning my comment about our series being pretty boring if only SWMs and Yamahas are competing. Though I fully realize that Vintage Trials must evolve as new, younger members join, and ride the bikes they grew up with...still I hate to see the disappearance of the older bikes. These are the bikes that spectators and riders alike take a special interest in.
When I first joined MAVT, Bowie Pearre, who was it's head at the time, actively approached people he thought willing to ride the older Vintage class bikes. He convinced me to put away my late model Sherpa T for a BSA Victor, and then later to ride a 1955 Matchless (heavyweight) G3 (350cc). Though I enjoyed competing on the G3, within a year or so there was no one else in the class on a heavyweight, and my thoughts turned to a 4-speed Sherpa T. I sold the Matchless and bought a Model 10 Bultaco. Still wishing to compete in the Vintage class, I now had the "SWM" of the Vintage class bikes.
Somehow, my thoughts kept going back to the heavyweight. When I learned of a BSA Goldstar trials project that was for sale, I sold my Bultaco to justify the purchase to my wife. Alas, the Goldstar turned into an iron barreled B33 and I decided not to buy it. But I was now hooked on finding a heavyweight, and so the search in earnest began.
What I wanted, was a 500cc Alloy top end AJS/Matchless, Ariel, or BSA. What I found were price tags I could not afford considering I would also be looking for a lightweight trials frame to make the bike even a little competitive on the three line I hoped to compete on.
Okay, so enough of my ramblings, this is where the project starts, with the acquisition of a 1948 AJS 500cc competition bike. As the photos below show, not the most attractive bike on the planet.
This bike turned out to be quite a mongrel, which is no doubt why the price was "reasonable". It was titled as a 1948 AJS, but the only things 1948 about it turned out to be the bottom end, and the transmission, The bottom end was actually from a Matchless G80. The top end was a 1949 AJS as was the frame. However, the rear sub frame was early fifties as 1949 only offered a hard tail for competition. The front end was from a late fifties BSA, and though it appeared to fit, well... that's another story.
I was not dismayed however. There is something about taking anything headed to the dump and turning it into a Trials bike that gets my blood pumping. I had a project, and that is what was important. After all, I only had two other unfinished projects at the time, and I didn't want to take the chance of being "projectless", a fate no doubt worse than death.
Here's the motor in all its glory. 48/G80 means this bottom end is from a Matchless. If it were stamped 48/18 it would have been AJS. No alloy top end, or even an alloy head, but things would begin to get better. Turns out the '48 bottom end had a '49 top end, which could take the early fifties alloy head. After taking off the iron head I realized the weight reduction would be considerable. Here, the engine sprocket is a 16 tooth. These were stock on the 350cc trials models. AMC offered a 15 tooth at the time, but I have not been able to locate one (yet).
Okay, so on with the story. So far I had an engine with a magneto. Oh, but to back up a bit, when I bought this bike I was assured it ran. However, when delivered, the seller confessed that he had not been able to start it due to (most likely he said) a dirty carburetor. Just another challenge, right? These old singles have pretty much the same starting technique, so I thought I should at least give it a try. First, remove the gas cap and smell... Oh my, really old gas. My first thought was, the seller is probably right only if I'm really lucky. Anyway, I slowly engaged the kickstarter and with clutch pulled in, kicked it a few kicks to make sure the clutch was not engaged. All was well there. Then, I eased the piston just over top, dead center... opened the throttle and "tickled" the Amal monoblock until fuel squirted out the tickler. Re-engaged the kickstarter and meditiated on kicking for at least thirty seconds. Now, with all things focused on swinging through compression, I give it my best shot........Nothing! Okay, one more try.... Up over compression, open throttle, tickle, meditate and kick!!! Houston, we have lift off!!! The motor instantly settled into a putt putt putt purr. The motor is quiet, the carb is okay and so off I go on a short "test ride". The only thing better than this moment will be that first trials section.
Now I've got a running motor. Just a call to Sammy Miller, for a replica Ariel HT5 frame that I plan to modify for the AJS motor and I'll be off and running. Only one problem here: Sammy no longer makes (actually, has made for him) the Ariel frame due to "lack of interest". Talk about a day late... seems last years catalog hailed this frame's virtues etc... Oh well, back to the drawing board...
After many fruitless calls, unanswered e-mails and "Sorry, we can't help yous", I did find a chrome moly motocross frame (only one) in England that was made for Matchless/AJS. The steering head was so well gussetted, I knew it would be a nightmare to try to modify it for trials. Still I gave it a lot of thought and almost went for it. It weighed a mere 19 lbs. with 10 inches of ground clearance, somewhat more than my G3's 6 inches of ground clearance. Finally, there was a possibility. Steven Surbey of AMC Classic Spares in England, had a customer who had made trials frames for these bikes. However, when Steven made contact he found out the gentleman had retired from frame making. Again, a day late...
Eventually, Howard Fawkes of Faber Frames, maker of the Otter frames, gave me the e-mail address of someone who knew someone who made trials frames for AJS/Matchless. I wrote an e-mail and waited for a reply. No reply.... Later, Howard found the phone number for Andy Bamford, the actual frame maker. He was not hooked up to the internet, so I made the call to England. Finally, success!!!! Yes, he could make me a replica trials frame. No it was not of chrome moly, but it was only ten lbs more, a total weight of twenty-nine lbs including the swing arm. And to finally make this long story short(er), Andy has a great reputation in England with some of the most successful pre '65 riders using his frames. He also makes alloy engine plates, silencers and center mount oil tanks, all of which I need. In about four months everything is done and is being shipped to me. Andy has even made adapters for me to use tapered roller bearings with a Betor front end. Not very British, nor acceptable in England, but he makes the change anyway.
Here are the components I received from Andy Bamford . The frame is basically a replica of the 1964 AJS/Matchless competition trials frame the factory made. The quality of the frame and other parts Andy fabricates is top notch, and the prices are very reasonable. All in the photo was delivered to me for under $1,900.00.
So now the real fun can begin. The top end is currently with Tim Taylor, who is putting new valves in the replacement alloy head. I have just finished putting trials gears in the Burman gear box. I'll continue with this article as the pieces start going together. Hopefully, that will be very soon.
AJS Heavyweight Project: Trying To Keep the "Vintage" Alive
I was very impressed with the quality of Andy Bamford's work. The bend in the tube here is the reason Andy does not use Chrome Moly. After the flux is cleaned up, the frame will be ready for primer and paint. I'm going to prime first and then put things together, checking for fit. Once all goes together right I'll paint it.
With the frame painted, the bottom end and the mag cleaned up, the bike is beginning to come together. Here, the engine plate still needs to be polished. Steering triple clamps are in place and ready for the front end.
Still waiting for the head to be done. The alloy head was "pulled from the pile" without knowing it had an oversized exhaust valve guide, almost impossible to find. However, it turned out to be okay and was put back in the head for use. After being outbid numerous times on ebay trying to get a stock, steel tank, I found this fiberglass one in Sammy Miller's catalog. It's lightweight, shaped right, priced right, and most of all, replaceable.
So far, the only machine work I've needed has been to lengthen the steering stem on the triple tree. These frames are made to accept a Norton front end, used by most of the British riders. Andy modified it slightly and made alloy adapters, top and bottom to accept tapered roller bearings for my Betor forks. The steering stem needed to be lengthened by about an inch. I lost about 1/2" of ground clearance with the raising of the top clamp, but these triple clamps bring the fork legs much closer to the steering head than the Norton forks would be.
Hopefully, progress will speed up now on this project. I have almost everything I need to finish it except time. I'm still gathering British bolts and studs to fix things to the frame, and haven't figured out what size sprocket to get for the rear. With the trials gears and 16 tooth engine sprocket, this bike is already geared lower than the stock trials bike (500cc) of that era. However, our sections are nothing like the straighter sections it was made to ride. I'm going on the premise that I probably cannot gear this bike too low no matter what size sprocket I use. Be back soon with more (I hope).
I got the AJS tank Stickers from ebay. The magneto is now timed: fully advanced is 1/2" BTDC, making the retarded position just about TDC. This bike should not kick back if the proper starting technique is used.
The folding foot pegs and rear brake pedal came with the frame. The front facing chain tensioner was easier to mount than working out one to face the rear. This side of the engine and transmission is now ready for the clutch and primary drive.
The timing is adjusted by loosening and moving the taper fit gear at the end of the magneto shaft. This is now covered by the magneto chain cover with the AJS emblem. The rocker box cover is off awaiting some "pre-starting" top end lubrication. Nuts and lock nuts adjust the length of the push rods for "valve clearance". No feeler guage is needed. No play is called for, but the push rods should spin easily at TDC on the compression stroke.
Here. the engine is complete. It is just waiting for a new carburettor and the silencer, which will have to be modified due to the curve in the exhaust pipe which is different from the one the silencer is made for. In piecing together an old bike like this, that is often the challenge, making something fit and work properly. The transmission is reminiscent of a "Skull and Crossbones" in this photo. The original kickstarter did not fold, so a Triumph top was welded onto it. The shifter was given a BSA extension with the end turned inward rather than out. It was repositioned for the right boot toe. Down for first, up for the rest (four speed). So I'm getting closer. I still need a carb, tires, a rear sprocket and a few miscellaneous "bits". Looks like it won't be ready this season, but hopefully I'll have it together and the "bugs" worked out for next season. More coming soon (I hope).
The kickstarter did not quite clear the right foot peg. The peg needs to be held "up" for the kickstarter to pass. I wanted to make this quick and easy so I decided to drill two holes in the peg itself and use one hole to hold the peg up. The other hole is just a place to keep the "pin". Now I just reach down and move the pin to the other hole. After the bike is running I return the pin to the "holding hole". I'm open to suggestions as to how to improve this set up. Ease of operation and neatness count big.
The primary side is now together. Many thanks to Warren Kleis for the many Matchless parts he gave me. The clutch is made up of plates from both his and mine. I had long sought after the elusive 15 tooth engine sprocket, and was told by parts suppliers in England that they simply did not exist any more. Warren's bike is a war model, which came with, and still had it; the smallest sprocket made for the end of the crank. Now I have a feeling I went overboard ordering a 70 tooth rear. I have a feeling that the right gearing will be with a rear sprocket having somewhere around 60 teeth. Fortunately, Sprocket Specialists makes any size you want (48-70). Carb, tires, oil lines...we're getting close.
Okay, now we're rolling again. The bike now has Betor gas rear shocks (14"), a trials seat (Sammy Miller), front end (Bultaco Betor), wheels and hubs (again, Bultaco), chrome 6" rise handlebars (Sammy Miller), an exhaust pipe, which was given to me several years ago by Chris Reen, who didn't know what it went to (boy was I pleasantly surprised), and last but not least, the alloy head with new valves.
Note: This article was getting out of hand (size wise) so I have replaced the large photos with thumbnails. Simply click on the photos to the left to see the full sized photo.
Here the tank and seat are final secured, I've fashioned a brake rod of 1/4" stainless steel rod, (I may live to regret the bend in it.), it has a rear brake stay made from a stainless steel shelf bracket, and the primary cover is attached. I was filling the primary the slow and clean way so I had time to look at and size this photo on the computer, I thought. I'll just say that I discovered the primary does not quite hold the 250cc that were in the container. One note here about these bikes. After assembling the motor etc... on this bike I can see why British bikes have a reputation for leaking oil. I lost count of the number of places oil is likely to seep from. Speaking of oil, I found a Norton spin on oil filter unit with a Fram filter on ebay. I looked for literally hours, trying to find a good place to put it. Other than hanging off the frame somewhere, it turned out that if placed just right under the seat on the rear fender, the hose connections were in a good place, and I could actually remove and replace the filter easily. I have plugged the bottom inlet hole on the center mount oil tank and instead, returned the oil through the vent on top. This meant drilling a small hole in the cap for a vent. Clear tubing lets me see if oil is returning to the tank.
Turns out the small vent hole in the oil tank cap was another source of oil spewing out. I made the vent hole a little larger and counter bored it to fit a sleeve a hose could fit onto. That appears to have fixed the oil leakage. Tank now breathes, but keeps oil inside, where it belongs. Note: Apparant alligator on tank is reflection of tree bark.
I am temporarily using the 54 tooth 520 sprocket from my Bultaco to try to finalize rear sprocket size. The bike is geared low enough with this to handle all but the tightest of sections. The problem is; the front wheel will not lift at such low rpms. I have ordered a 60 tooth sprocket from Sprocket Specialists that I believe will help the situation some. This bike will wheelie at higher rpms, but it does take effort. The long stroke motor is slow to rev, nothing like a short stroke, two-stroke. I will post a photo of the 70 tooth sprocket I got for the AJS, but it's a monster (would require moving the chain tensioner further forward). I may try it at some point, but it looks a bit ridiculous, almost like you could take off the tire and run on the sprocket. In hind sight, I probably could have modified a gearbox sprocket for the AJ to give it less than 16 teeth, thereby reducing the size of the rear sprocket. I could have also machined it from a 530 to a 520. However, changing the gearbox sprocket requires removing the clutch and gearbox main shaft. For now, Sprocket Specialists is kind enough to make the Bultaco rear as a 530 so the front and rear match.
The only thing missing here is the silencer, which was sent off to be rechromed after I had the inlet moved from the bottom front to the top front so it would fit. This "free" pipe, that I was so happy to have, has actually cost me more in modifications than a new pipe would have cost. However, my pipe doesn't cover the AJS logo on the magneto cover like the other pipe does, and it sets it slightly apart from other bikes using the "Bamford" frame and accessories. One of my little quirks is that I don't like to have things like everyone else.
I like to be a little different (some would say more than a little).
Surrey Cycles provided the 26mm Amal concentric carb. My hat is off to the man who jets these. I told him of the engine I had, and that it would be used for trials. It came jetted "perfectly". I'm sorry I don't remember his name. I'll find it out so I can thank him here. Thanks to Steven Surbey of AMC Classic Spares for pointing me to him. The carb has a chromed slide to reduce wear. Unlike some people, I have no problem with Amals. They are easy to tune and dial-in. They may wear quicker than Mikunis, but I've kept 30 year old Amals going with just slide, needles and needle jet replacements. Filter is a K&N. Thanks to Bill Viney (MAVT member) of C&L Cycles for helping me find it.
Note: This Amal carb did not have a "seap hole" for the tickler. When getting ready to start this bike, I tickled it until it started laughing (very poor pun), but no gas seaped out. Noticing the lack of a hole, and the lack of gas seapage, I drilled my own hole, which fixed the problem. Seemed like the right thing to do.
The bike is now complete (with chrome silencer and 60 tooth rear sprocket) and I've had a chance to ride some practice sections with it. So far, I'm very impressed. The gearing feels good. The AJ will putt along at a snail's pace for tight turns, and won't run out of revs when a little speed is desired. There is plenty of power, it just can't be dialed on instantly from a near stop like a two-stroke. Steering is very light and neutral, and the bike turns very well. With the heavy engine and gearbox the weight bias is toward the front, so rider weight must be kept back much of the time. Weighting the front end in turns to keep the bike from "plowing" is not usually needed. Even during climbs it is often necessary to keep weight back to keep traction. With the weight on the AJ being high and forward, it is not as forgiving of poor body position. I'm hoping it will make a better rider out of me. Either that, or you'll see me footing and falling all over the place next Spring.
In closing I'll pass on thoughts inspired by my wife when she asked me, "Was it worth it?" This particular project cost between $7,000 and $7,500 to bring to completion. I could have bought five or so newer, ready to ride bikes for the same price. However, I get a lot of satisfaction watching a bike transform into something functional, and to my eye, beautiful. The search for the right bike to start with and the thoughts and ideas of how to put it all together make this about a three year project. In this case the "end has justified the means". I'm very pleased with the results, and happy to keep a little piece of pre '65 Trials alive. These were "the bikes to beat" before Sammy Miller introduced the Model 10 Bultaco. I'm certainly not going to be "the rider to beat" on the AJS, but I hope to have a lot of fun on the three line with it. So, yes, it was well worth it. If there is anyone else out there interested in a similar project I'll be happy to pass along whatever I have learned throughout this project. I can be reached by phone at (410) 635-6722 or contacted through this web site.
