Mid 60's Bultaco Matador Project

Hey all... I'm in the middle of restoring a mid 60's Bultaco Matador. Using the serial number the bikes been dated from 1964 to 1966, sure would be cool to really know how old it is.

My short term plan is to try and get this bike ready to ride vintage trials this coming summer. The bike actually belongs to a friend of mine, but since I'm building it for him, he said I could ride it for the next couple of years, if I wanted.

I'll try to get some pictures up as I get a little further along on this project

I have another 65' Matador in pieces, that I own, and hope to put it together when I get done with this one. That one I hope to do some trail riding with and maybe use it as my vintage dual sport bike.

Anyway this is my first ever attempt at restoring a motorcycle. I have most of the pieces and the motor was put together, but I had to open it up and clean it out because the main bearings were frozen. My plan is to take every last nut and bolt off, clean, powder coat, paint and polish and repair everything that is broken.

I got the motor completely apart, replaced the bearings, seals, gaskets and so on. Got everything all nice and clean and put it back together... Now it doesn't shift. Actually I don't know if it ever shifted, because it was frozen, but now when I push down or lift up the shifter, it feels like its shifting, but it's not. With the case open I was able to make everything work by hand, but when I put the case together the "wishbone" doesn't seem to turn the shifting wheel inside. Is there anybody out there that knows what I am talking about and might give me some ideas as to what is going on?

what model #?
is this a 5 speed?

if so, you have to be careful about the orientation of the middle shift fork. if you put it in backwards it will shift when the case is open, but not when closed.

did you try turning the output shaft while you shift it to help the dogs engage/shift drum move along? was the shift drum notched or have any damage? did you install the drum so it's lined up with the corrrect notch for the neutral detent?

if it's a 4 speed, i'm not familiar with them.....i know the 4 speed has a selector plate like the old single british bikes....

i'm sure you don't have a pic of the trans assembled with the case halves apart - that would help. when you say wishbone/shifting wheel- that sounds like a 4 speed - 5 speed has shift drum and spring loaded shift pawls

If the bike is a mid '60s then it is a 4 speed. I'm thinkin' the 5 speeds didn't come out till the late '60s around 68 or 9. I've got a '66 Matador in the basement . It's waiting till I retire to be rebuilt.

If this helps then fine. In 1964 I bought a El Monterdairo. (bad spelling)
I lived in Spain at the time. It was a 4 speed, 350 or 360 cc.
The owner of the shop said it was the biggest motor at the time for Bultaco & used a proven transmission. I think that means the trans was an old design & motor was a recent design.

the montedero is a right kicker - i would think the trans would be different. maybe not.

as for proven transmission, i think the only thing proven about them is that you are proven to find neutral in between every gear :)

I had the 175cc version of your bike. It was a 1965 Campera and it was a 4-speed. The transmission must have been straight off a trials bike since it had 3 very low gears with a huge jump up to 4th.

Can't help with your problem since mine ran perfectly for the three years I had it so there was no reason to take it apart. I absolutely loved the tractability and torque of that engine and the suspension and handling were top-notch for the time. You'll enjoy it once you get it sorted out.

My understanding was that Bultaco basically made one engine but used different top ends for the different displacements and changed porting and flywheel weights for the different models.

Thanks for your replies so far... The motor is a 4 speed 250cc. I've been told that all the motors of that era had the same bottom end. There was a 175cc like the Campera that was mentioned and there was a 200cc as well. Pretty much change out the cylinder and you got the other sizes. Interchangeable parts, what a great idea!!

So it looks like I've solved one of my problems, the fork that comes off the shifter appears to have been bent about 1/8 inch and wasn't coming in contact with the "fingers" on the gear selector plate.

That leaves 2 more problems:
1. It is really hard to make it shift. I seem to be able to get it in all the gears, but I really have to fiddle with the shift lever to make it work. Sometimes it drops right in, but most of the time I have to move it back and forth before it will go to the next gear. I think there is a combination of things causing this, but it's kind of hard to pin-point what's really going on because to get everything in place so it will shift, you have to close it all up and you can't look inside to see what's going on. The slots in the gear shifter place are a bit worn and the pin that rides in the slot is worn as well, so I'm guessing things could hang up there. Also the shifting forks ends and the grooves they ride in are pretty worn as well, causing things to be a bit sticky.

2. The shafts are really hard to turn around. I have replaced all the bearings and it is well oiled, but when I stuck a drill on one end of the shaft to spin it around, it took a great deal of torque to get it to move.

BTW- I do have pictures of the inside, and was going to post them tonight, but left the camera in the workshop so can't get it till tomorrow.

I have some spare parts so will look through them to see if I can find some parts that are not as well worn to see if that will help with the shifting, but not sure what to do with the "binding" of the shafts.

To make this post a little more interesting here are some pictures of the project.

For some reason I didn't shoot any before shots of the bike I am currently working on, but here are some pictures of my other bike I plan to build later. The current bike was in similar shape:








This is what I hope the finished bike will look like...

BTW - I'm actually going with a different color for the frame so I will probably look more like a Sherpa when I'm done. Here's a slightly newer one.

shafts should be easy to turn by hand! no drill required! did you get the bearings/shafts in straight and not cocked? when you put the cases back together did it take alot of force? some force may be necessary on the crank bearings, but the transmission side should go together quite easily - the fit is not as tight on transmission bearings like it is on crank bearings.. i think you got it all jammed up/warped/binding/something interfering. if you gotta split it again, put it together without the crank in there and see how it goes together - it should be very smooth.

when you reassemble cases, you can pretty much tell if you got it wrong. if it's really difficult to get the last 1/4" - 1/2" of the cases together, something is wrong. for lack of a better description - it sometimes takes a little fiddling to get everything lined up, but once it's all correct, it will just go together easily like it was never apart, and was meant to be together.

if the shafts don't spin easily it'll never shift. any wear or slop in any shift parts will make it not shift properly. there is very little room for error in a shift selector.

Here's some pictures before I put it back together....

The main crank doesn't look as nice as the other parts, but that is the only part that runs smoothly.

Wow great work,

Astonishing too me that you haven't had any problems with the rod bearings many get rough by the time, expecially the lower one.

Gearbox had no problems either, often the shims beetween the gearsprockets are worn?

Any special treatment to the engine cases, I like the dull finish.

Very cool!

I split the engine case back open yesterday and found that there was only one bearing at the bottom that was hard to turn around. I pulled the shaft out that was going through the bearing and re-seated the bearing.

The way it says to put the case together is to put everything into one side, including the bearings that will be in the other half of the case. then heat that other case up and slide everything together. That's the way I did it the first couple of times. So this time I put the bearings in both of the cases, then with a torch, heated the one bearing that was the tightest fit, and tapped everything together. I think this is what made the difference because doing it the "proper" way caused the bearings to not seat completely into the case, my way everything appears to be where it belongs. I also polished some of the ends of the shifting forks and the "cam" slot they ride in, plus I polished a cam that is used in the kick starter section.

Got the whole thing together and the result of all this is that everything seems to be working like it should.

Now on to the cylinder, head and piston...

Does anybody know how I can get a couple of "frozen" piston rings off an aluminum piston, without destroying the piston??

I would like to step back a little and bring this project up to date by giving you a little back story.

Last summer, my friend Dave, got me down to the vintage motorcycle trials and motor-cross. It was one of the most fun weekends I've had in a long time. I've always wanted to have a trials bike, but the stars never lined up correctly and it never happened. A few weeks later, at a second show, I knew I wanted to get a bike and was lucky enough to meet a guy who had what I was looking for. My hope was to find something I could restore, from the ground up, and that's just what he had. (see the pictures on a previous post). With the purchase of this "new" bike in process I got a surprise when Dave offered to give me a bike to ride, for as long as I wanted. All I had to do was "restore" it. So that's how I ended up with 2 65' Bultacos to restore.

OK... now how does somebody, who has never restored a bike, go about setting up a workshop and learn the skills to take on such a task. First let me say, I'm a pretty handy guy, having built many things over the years. I've also spent some time in a machine and sheet-metal shop, where I picked up a few skills. On top of that I have been a potter for about 40 years. So I'm pretty good with my hands and have a far amount of tools. So I figure, how hard could it be.

Here's a list of skills and tools I wanted to put together for this project:
1. Welding - I'm not a great welder, but over the years I've learned how to stick steel together with a torch or wire welder. Last year someone loaned me both a gas welding rig and a big MIG welder (check)
2. Painting - I've done a lot of spraying in my pottery business, but that is very different from what I would need for restoring bikes. However, I do have a small spray booth and a compressor (more on this later). I still need a lot of work on this.
3. Powder Coating - I've read a lot about powder coating and it seems like a really good idea, but I don't think I can afford to pay someone else to do it. So I found a gun that was better than the bottom end guns, but is not as expensive as a pro gun. I find the application is very similar to spaying pottery glaze and I have ended up using a pottery kiln to cure the powder coating (works really good).
4. Polishing Metal - It is amazing how bright you can shine up a piece of steel or aluminum. I'm still trying to figure this out, but I've had a couple of things turn out pretty nice. I did have to get a polishing wheel.
5. Media Blasting - Now here's a challenge. Blast cabinet, got a cheap one from Harbor Freight that is sort of OK, but leaks a lot. Also got a "tank blaster" to do things that won't fit in the cabinet and "soda" blaster for the carburetor and other "fine" parts.

I'll come back to some other tools and things later, but this is a good time to talk about problems.

1. My original compressor didn't make nearly enough pressure or volume to run a blaster, so I needed a new compressor. In the end I actually need to tie both my compressors together to get enough power to run the blaster.
2. Powder Coating and probably painting (I haven't gotten into this yet) require extremely "clean" air. That means NO water, NO oil, or any other little bits of things. I spent nearly a whole month trying to get my powder coating to work without "fish-eyes". I ended up installing 4-5 filters and water extractors but I finally have really clean air.
3. Polishing has something to do with magic!! I have been able to get a few things up to the level I want them but right when I think I have it figured out, the next piece doesn't work.

So over the last couple of months I have been learning how to polish, powder coat, weld, and blast, as well as tear a motor completely down and put it back together (well I'm in the process). Can't wait to have the motor up and running and then I get to learn about shocks and forks and wheel hubs and brakes and all the other things.

The cool thing about working on a Bultaco is that it is about as simple as it gets, but the final product should be an incredibly fun bike to ride.

If anybody is interested I will go into detail, with photos, to show the good and bad of my progress.

Take the piston to your local engine and carb repair shop, they should have an ultra sonic cleaner, this works best without damage.

You will get any other debries stuff that might stick on the piston.
Cost are low only a couple of € / $. I would give them your carb for cleaning too.

Is the piston of the engine still in the spec's and not worn out? Sounds special for me because your Bultaco is an old lady much older then mine and I had serious isues in the engine department and the bike had not been used much, found it in an italian online flea market page, stood between 15 to 20 years in a garage, (a model 199b). All engine bearings,
where rough, piston was to the limit, lot of carbonate everywhere.

Interesting story about your tools, all these things I don't have the space in my garage like blasting, powder coating and where I don't have the skills yet is welding.

Polishing is no problem but very time consuming and messy, I like the result but not the process.

One thing I had to discover, there where some parts that had to be redone by milling and on a lathe. I've got now a milling and drilling machine, (an insrued loss), but still need a small lathe for shims, ...

I will keep on tracking your restauration, very interesting, while I by myself restore my trialsbike.

Once I understood how the rings actually go on, I was able to knock them off with a very small cold chisel. I took the tip and was able to catch an edge of the ring and bang it open. I did soak the top of the piston and the rings in Marvel Mystery Oil over night. The rings, with just a little resistance, slid out of the grooves and broke, but that's OK because I wanted to replace them anyway.

I kind of messed up gaping the ring end and took too much off so I had to order a new one. Remember I have to keep thinking metric. Anyway things are on hold with getting the piston so I was torquing and lock tighting some of the bolts and nuts before they got buried under the fly wheel and clutch and so on and sheered a bolt off. So off to the store in the morning to get some kind of extractor tool, also pretty sure I cross threaded this particular bolt, which I rarely do, but when you are screwing steel into aluminum you got to be careful.

I've been pretty fortunate with this motor so far. There is some wear, but in general it's in pretty good condition. I did replace all the bearings and oils seals, but there is one bushing I probably should have replaced but didn't. It's on the kick start gear so hopefully it will be OK.

I don't have a lot of tools to check for tolerances so I'm hoping that because things don't look too worn that means they should work. Since this is going to be a Trials bike and won't be pushing any limits I figure I can be a little more loose on the build. The guy I'm building the bike for doesn't seem to be too concerned about the tolerances.

I got some powder coating on the cylinder body and things are looking pretty good. I'll try to post some more pictures tomorrow.

The metric is fortunatly for me no problem as I live in the metric world, (your feets inches and so on are for me a big problem because they have no math consistance!).

Never trust old and rusty bolts, if they have the bultaco logo on the head or the strengh numbers then it's OK, Bultaco screws have 800 N/mm² the normal one we use here in Europe have printed 8.8 on the head, whitch is also 800 N/mm². Most screws without number stamped on the head have mostly only 400 -500 N/mm² (strengh class in metric 5.6 or 4.6).

Getting in touch with theese and using the torque for higher quality bolts will sheere of the screw.

I also have only limited tools for measuring wear only the basics everyone should have, like a caliper, protractor amd guides. When it comes to bearings I feel the smoothness, when they go smooth and no gap is feelable they are OK if not they have to go.

When I'am unsure I take them to my shop for proper measurement.

Showing some pic's would be nice.

The Buls and Montesa's have to be the best looking bikes made back then. I was at a vintage meet and there were a handful of the Spanish iron, really stood out from everything else there.

Jello mold head; haven't seen one of those in years...

It helps to tool up, measuring stuff, it's way cheaper to buy that stuff today than it was back in the day. It saves a lot of time not having to put it together and tear it down to find out if it works.

These early motors have a lot of character!!

Prices have really come down on some of this stuff. I have an old Brown and Sharpe Dial Caliper that must have cost over $150 when I got it, that's about $300-$400 in today's money. I saw a cheap little digital caliper for $15 the other day. Just for grins I checked on a new Brown and Sharpe and I could get one for $230.


Been sick for last couple of days so works been pretty slow.

Here's what the motor looked like before I started working on it:





Note: This is actually a different motor, but this is what my motor looked like when I started.

I was putting lock-tite and getting all the case nuts and bolts to the right torque before putting on the clutch, fly wheel, magneto and Drive gear, and broke a bolt. Got a new easy-out set and finally got the bolt out in 3 separate chunks.

So today I got the clutch installed.

Here's the clutch baskets and flywheel before I installed the plates:



The clutch plates are a bit beat up:



I ground off the burrs and cleaned things up the best I could. Hopefully that will be enough to get things working, but I can always go back in and clean that up later, if I need to.

Here's a picture of the finished clutch:


Also powder coated the barrel:




I stuck the barrel and head on just to see what it would look like:






The stand I built to work on the motor:



If I can, I will build the tools I need, like this stand. I also built a tool to help me separate the cases, but I forgot to get a picture of it today.

One of the more difficult things I have had to deal with is getting the bearings off. Couldn't figure out how to build a good puller so I got a cool one from Sears that works really well. The jaws clamp down on the bearing so they don't slip off.



Even more difficult was a tool that could pull a bearing from the inside. I tried to fabricate one from a carriage bolt, but it didn't work, so I got this one from Harbor Freight.



You just slip the right sized end through the center of the bearing, expand it out till it grabs it, then hook the slide hammer on and bang it out. Works Great!!

Still waiting for my replacement ring to come so I can stick the piston on. Things seem to be going together pretty well so I'm hoping it will work when I get it done.

Here's a picture of the swing arm I powder coated the other day. I'm pretty excited at how well the powder coating is coming out. Just for grins I polished the brass bushing on the end and painted a little clear coat over the top.