Build a Bultaco TSS from scratch

[blaine.hale]

First off, sorry to disappoint ya'll with nothing to bring to the table in this thread.

Really what this thread will be about is the acquisition of knowledge and a collaborative of minds here on what I'd like to build in the future (after that first time home buyer bill slows down.)
The basic question would be: What is the cheapest way to piece together a Bultaco TSS racer?
A REAL TSS will cost quite a bit of change, of course. What I'm looking to do is pull a frame from one of their street models, pull an engine from another (I know the matador engine is close to metralla spec) and kind of piece together a cheap franken-taco to take out to track days.
So what would be the best and cheapest frame to steal from and what would be the best and cheapest engine to steal? Liquid cooling would be cool but I think only the TSS really ran those engines? That would be majorly expensive.
We'll throw some pics in along the way!
Join in on the conversation with thoughts and what not, please!

[edray]

i think this is brilliant..
i,too, always loved the metrallas, lusted after one i saw w/ an america kit on it..now so crazy expensive..as usual was hoping for my lottery dreams to come in,sigh, when kenny roberts's Metralla was on ebay, twenty grand, and of course if i had it i'd do it..jeeeesh.
air tech has a fiberglass Americas kit available...
up here in washington state,theres rumors, hopefully true; that you can register anything as long as it has road equiptment on it..
great idea. i'll be watching,,where's that little popcorn guy??

[pommie john]

I don't know a lot about Bullis but I have a couple of friends who race them.
One has a genuine TSS the other has a road race 'crosser. I think he uses a Pursang engine.

The TSS has been converted to air cooling because the water cooled one has no water pump and a large volume of water in the radiator. The problem he had was cold seizures 'cos it took so long to warm up. He had to take a tea urn into the pits and fill the radiator with hot water before each race.

The Pursang seems very reliable and quick.

I'll see if I can dig out some photos.

[blaine.hale]

Originally Posted by pommie john

I don't know a lot about Bullis but I have a couple of friends who race them.
One has a genuine TSS the other has a road race 'crosser. I think he uses a Pursang engine.

The TSS has been converted to air cooling because the water cooled one has no water pump and a large volume of water in the radiator. The problem he had was cold seizures 'cos it took so long to warm up. He had to take a tea urn into the pits and fill the radiator with hot water before each race.

The Pursang seems very reliable and quick.

I'll see if I can dig out some photos.

So the way I understand it with how the Bultaco liquid cooling works is that it was thermo-syphon...not on a pump system. It normally had to get up to about 70 degrees celsius before you could really get on the throttle. This meant the rider had to watch a little temp gauge and wait for that magic number. The Buls at the time also used electronic ignitions, which I'm really interested in sourcing as well but they range around $300+ area.

I've read the Pursang motor would be my best bet for power output so I may look at picking up a parts bike pursang or just the engine.
I think this is all pretty doable on a budget if its a bitsa bike. The most expensive part is, ironically, the body work. That fiberglass isn't so cheap haha. I've already found the place to get the right body work.

I've got more knowledge and theory to add to this but I need to find out the most practical engine and frame.
I should give Hugh's a call and get their thoughts too :)

[pommie john]

Only photo I can find at the moment

[stainlesscycle]

i got pursang bits by the buttload. since you're gonna take the whole thing apart anyways, (why would you do it any other way) i surely have a seized motor and bad top end here somewhere - probably have frames (i know i have 2 model 67 and 2 model 68 and a few 135 i believe.., wheels, etc. a big box o parts to tinker with. motoplat ignitions go for around $100 - $150. femsa's about the same (coil must match stator though)....

body work won't be cheap. building the motor say $1000 tops (that's new crank, bearings, seals, piston, bore, etc.).


finding a watercooled motor would be the best for 'wow factor' but they're pretty cost prohibitive..

[PSchrauber]

Good thought's and the Pursang engine was used for the TTS models too, expecially for the 24h races they used the 350 360 370 cc engine???, (have to look up the details). These bikes where called Montjuic and the first ones where also air cooled, so you skip the costly water cooling, (expecially cylinder/cylinderhead and radiator!).



To the fiberglas body work, look up specialists for this, so you really get the good quality in craftmanship and durability and of course the used materials are resistant to the fuel, (expect to pay some money for this). I have ordered and got a custum made gas tank for my Sherpa. I'am very pleased with the outcome, as the man that made this have the right molds. (*) The paint job should be done by someone else.

Original electronical ignition systems might still be available as NOS parts, but expect a much higher price. There are also replicas availalbe but I don't know if they will fit to Pursangs. (*)

Very importat the right exhaust system for the engine, this is smething you will have to find an expert too, it's a two stroke and then additional a racing machine, there are some ressources in Europe available, sadly they speak only Spanish. (*)

The reminig rest is pretty standard, apart from the controls for hands and feet.

(*) If you are interested PM

[blaine.hale]

This is all pretty in line with what I was thinking as far as motor rebuild and body work. It seems the Pursang motor is the way to go on this so I'm calling what sources I have around Atlanta and putting up a CL ad to see what crazies I get calling me, haha.
My question about the Pursang motor, specifically, is what set it apart from the others...the Matador motor, for example? Is there a specific year/model Pursang motor that is most preferred?

Thanks for all the info thus far! I'm sure I'll be reaching out to a few of you here that have mentioned having parts around.

[blaine.hale]

Just to keep the thread interesting and to cite my sources, here's a PDF I really enjoyed:

Bultaco TSS road test

(That link is a direct download for the PDF, don't worry about it being malicious.)

And of course, here's a great example of what I'd like to build...Only not as fancy and spensive :)
http://www.fantasyjunction.com/cars/...%20Model%2024-..

[stainlesscycle]

Originally Posted by blaine.hale

My question about the Pursang motor, specifically, is what set it apart from the others...the Matador motor, for example? Is there a specific year/model Pursang motor that is most preferred?

Thanks for all the info thus far! I'm sure I'll be reaching out to a few of you here that have mentioned having parts around.

the pursang motor at model 135 got bigger ports, and different head. at model 180 (i believe) they got bigger ports again, and a new head with gasket.

the pursang had lighter primary chain setup which let it spool up faster.

the port timing and heads are different on matador.

the pursangs scream at the top end, and are more race oriented- i.e. peaky. the matador is more torque oriented, and has much more bottom. i believe you could make a matador motor into a pursang motor with top end, clutch/primary change, and ignition (and you'd need to open up the transfer ports on the cases to match the pursang top end.)

in general the sharpa s and pursang were the fast/peaky motors..

[Abdelhub]

Originally Posted by stainlesscycle

the pursang motor at model 135 got bigger ports, and different head. at model 180 (i believe) they got bigger ports again, and a new head with gasket.

the pursang had lighter primary chain setup which let it spool up faster.

the port timing and heads are different on matador.

the pursangs scream at the top end, and are more race oriented- i.e. peaky. the matador is more torque oriented, and has much more bottom. i believe you could make a matador motor into a pursang motor with top end, clutch/primary change, and ignition (and you'd need to open up the transfer ports on the cases to match the pursang top end.)

in general the sharpa s and pursang were the fast/peaky motors..

Ive got a 104 model cylinder on an alpina....ports are very small for an mx motor...Id go for later models 75'up

Mike

[Abdelhub]

Originally Posted by PSchrauber

Good thought's and the Pursang engine was used for the TTS models too, expecially for the 24h races they used the 350 360 370 cc engine???, (have to look up the details). These bikes where called Montjuic and the first ones where also air cooled, so you skip the costly water cooling, (expecially cylinder/cylinderhead and radiator!).



To the fiberglas body work, look up specialists for this, so you really get the good quality in craftmanship and durability and of course the used materials are resistant to the fuel, (expect to pay some money for this). I have ordered and got a custum made gas tank for my Sherpa. I'am very pleased with the outcome, as the man that made this have the right molds. (*) The paint job should be done by someone else.

Original electronical ignition systems might still be available as NOS parts, but expect a much higher price. There are also replicas availalbe but I don't know if they will fit to Pursangs. (*)

Very importat the right exhaust system for the engine, this is smething you will have to find an expert too, it's a two stroke and then additional a racing machine, there are some ressources in Europe available, sadly they speak only Spanish. (*)

The reminig rest is pretty standard, apart from the controls for hands and feet.

(*) If you are interested PM

wow a center port cylinder bultaco.....Id love to get a cylinder like that....A lot of my projects are based on where the exhaust comes out of the cylinder.....Lets you use a full cradle frame.

Mike

[pommie john]

Originally Posted by PSchrauber

I think they got the spelling wrong. Surely it should be 24 Horrors



.

[Magnum1b]

I grew up in South Texas and there was a hole in the wall bike shop on Highway 83 in McAllen when I was growing up. Sometime in my teens I went in one day to drool and there was a new Metralla complete with the TSS fairing. Years later a friend from New Jersey regaled me with tales of his Metralla. That same year (in Austin ) I wandered into a BMW Dealership and there was a Munch Mammoth and a TSS Faired Metralla in the showroom. The Metralla was fully restored and beautiful to behold. I've never owned, or ridden one, but I have lusted for a couple in my years.

TCARS
Jack Ferguson
Ellenwood

ps: somewhere I have pictures of the "Austin" bike. I'll keep an eye out for them and post if I find them

[darmst6829]

Originally Posted by blaine.hale

First off, sorry to disappoint ya'll with nothing to bring to the table in this thread.

Really what this thread will be about is the acquisition of knowledge and a collaborative of minds here on what I'd like to build in the future (after that first time home buyer bill slows down.)
The basic question would be: What is the cheapest way to piece together a Bultaco TSS racer?

Fun! The trick is to use a Metralla frame with 35mm forks from any 70's Bultaco off roader. For the motor Bultaco made a 125cc that had a geared primary drive. I would try and find one of those then mate any 250 barrel that will fit off a hot MX bike. My buddy Ralph built one up last year and its sounds incredibly cool.
Dave