Reducing Weight Of Old Trials Bikes

[huntmaster]

I couldn't stand my Yamaha TY175 as a teenager for lack of power. I strongly prefered and rode better on the 250. Today I am well over 200 pounds and I have above average muscular strength. My cardio sucks but its improving. I liked TL-125's until I had to ride them up anything steep, or any situation where lots of power was needed.

The TY-175 was a good bike but like the TL-125 was a bit of a lost cause for me at 6'4" and 255 lbs. The TY-250 was a great bike however and probably would have been near as reliable and maintenance free but far more competitive for me then my old TL-250 for all those years. Still I was able to get a few good results with it over the years often to the chagrin of light weight two stroke riders, particular at events that played to the bikes strengths...where traction was marginal and hills were long and steep but with no stadium type obstacles! But the sad truth is my current pre-65 Ariel HT5 project weighs the same and feels similar in many ways to the Honda...but instead of competing with TY's and SWM's it competes with other old lumps with ground clearance best measured with a feeler guage!

[mr clean]

Accoding to Sammy Miller the bike has never been imported to UK, and they have no stuff for it. How typically Honda. They made excellent 300 to 360 cc works bikes with innovative designs, won major titles and put together top Trials teams. Then never made these bikes available to the public and tried to send the works bikes to the crusher????

So someone told meme that the RTL-300 motor is 3 inches shorter than the TL-250. The motor can be made to closely match this bike. First obtain an XL-350 motor. Have the XL-350 motor bored to the max, have a ultra short stroke crankshaft and con rod CUSTOM FABRICATED and put in. put all the gears and everything else from the TL-250 put into the XL-350 transmission. Use the XL-350 flywheel because its very heavy.

Replace as many of the internal engine parts and all nuts and bolts with CUSTOM FABRICATED titanium bits. Have the cylinder machined down and shortened several inches.

Have an SOHC Head made from scratch or see if something else might fit???????

In the end it can be modified to fit into an aftermarket TL-125 Frame because it is shorter.

It has been enough fun just to find an alloy exhaust for this thing. This will be lots of fun to get tuned and fitted properly. When ever someone says CUSTOM FABRICATED I get a pain in my wallet

If anyone can find a link or picture I would be intersted to see if anyone has actually done this successfully.

Is this real or BS?

Why do I see a lot more money and time going into this approach than I want to try?

Just buying a new 4RT is looking cheaper and easier... (and a little more competetive)

[huntmaster]

Just buying a new 4RT is looking cheaper and easier... (and a little more competetive)

Yes on all accounts I would say! And depending on where you ride...a radically altered TL may not even be vintage legal and after all that work you might end up competing against a 4RT et all anyway!

At least with the current four stroke... Honda & co. are finally sharing a competitive design with the public.

[dixie]

YOU HAVE USED WORDS OR A PHRASE WHICH ARE NOT PERMITTED ON THIS WEBSITE. PLEASE DELETE YOUR POST/TOPIC. DO NOT TRY TO CIRCUMVENT THE FILTERS IN PLACE ON THIS WEBSITE do a really nice book in the uk

its a pictoral history of twin shock

and there is a really nice looking alloy framed honda works bike

if youwant a light and legal ish twinshock copy that.

it was ridden by a japanese works rider,

[feetupfun]

Just buying a new 4RT is looking cheaper and easier... (and a little more competetive)

I'm glad you are coming to your senses on this.

Did you really think you could build a replica of a Honda works trials bike for less $$ than the cost of a modern production bike?

What you seemed to be seeking was a high spec bike with many custom built parts. For that you should expect to pay many times the price of a new current model trials bike (unless you provide the labour).

Twinshock can be an economical class to compete in but not if you want to ride a works replica special based on something as unlikely as a TL250.

[mr clean]

Well,

I started with trying to find some ways to make a TL-250 lighter.

I was interested in finding aftermarket lighter frames from the 70's, as vintage motocrossers have picked up BRAND NEW frames from back then for as little as $50, and in most cases less than $200. So, I thought there would be a few different types of lighter aftermarket frames out there somewhere. I have not yet got an answer to this one.

I also thought that the finding an quiet alloy exhaust system that would easily bolt on and drop considerable weight would be a fast and easy find. All I have got so far is someone offering a custom fabrication for $850US plus shipping. Ouch, and no thank you.

The Honda standard exhaust is very good, except for its high weight.

Also, The TL-250 weighs 218 lbs, so did the SWM Jumbo, and Italjet I think was heavier.

A late model Sherpa T weighs in at 204, so putting an alloy exhaust on the TL-250 gets rid of high up weight and brings it closer to the Sherpa weight.

Problem with the TL-250 is that so much of the weight is up high.

[mr clean]

As for the WES exhaust I now they stock them Here at BVM If there is nothing you want there gotta be worth a phone call too see if they can get one? And these people seem too focus on the older bikes and are EXCELLENT service Trialsbits

Hope this helps

Hi Barry,

I emailed BVM and still did not get a response. You work there?

[woody]

I don't think you will find any aftermarket weight saving parts for the TL250 in the UK due to them not being on sale in significant numbers. Very few were brought in as far as I know. Miller is the man who will know and if he doesn't sell anything for them, no-one will. Not sure he even made a hi-boy frame for the 250, just the 125. I am pretty certain there is no WES exhaust for them. The US specialists are your best bet and you can probably get stuff in Japan as their specialists did lots of home market improvements for Yamaha and Hondas that were never exported. Problem there is finding someone who can find out for you.

Just to get you going a bit more on what Honda could have done for its loyal and willing to pay fans, here is a photo of Rob Shepherd's RTL360 before Lejeune came on the scene. Now if only they had done few of these as replicas with a lightened version of the TL250 motor. Instead they did the Seeley in th UK to capitalise on the success the 360 enjoyed here. A lovely little bike but not as good as they could have done.

Then there is this, a bit of a mixed copy of a Fraser Honda and a works 305 (cross between Shepherd's and Marland Whaley's bikes) made out in Spain and finished in Honda factory colours I think. Nice

[feetupfun]

There is always the option of having a replica frame made but the cost factor is considerable and there are very few people willing to pay. There is lots of labour required to copy a frame and if the production run is only a few dozen frames as it would probably be for people who want to build a TL250 motor Seely replica, you could expect to pay $1500 US to $2000 US for each replica frame.

[huntmaster]

The US specialists are your best bet and you can probably get stuff in Japan as their specialists did lots of home market improvements for Yamaha and Hondas that were never exported. Problem there is finding someone who can find out for you.

The problem is that even the US aftermarket is pretty thin for the 250 and what is there focussing mostly on universal fit items, piston kits, OEM replacement type wear items like the hard-to-replace dished rear sprockets or in some cases side panels that everyone seems to be looking for. The bike is a little uncommon even in North America and I only came across a small handfull of others during the 15 years I rode mine in vintage events.

Considering the durability of the design I expect there are probably a lot more of them around then are still being ridden in competition. I lusted over pics of RTL's, works bikes, aftermarket Miller-type frames, etc., but there was no simply performance aftermarket for the bike. Ironically, due to the plentiful UK pre-65 aftermarket I wasn't able to do such a project until finding a 20 year older Ariel!

Doug

[mr clean]

Hey guys,

Thanks for this great stuff.

Someone pointed out to me that Supertrapp exhaust tailpipes ony weigh one pound and can be purchased new for $53.95 US.

So for someone that is crappy with a wench, er, wrench. I mean, spammer, er um spanner....

I am thinking of getting one of those and replacing the heavy second tailsection of the pipe. I will need to have a connecting pipe between the super trapp and the primary pipe.

I don't know how to bend or build a pipe. Any advice on how to do this, perhaps replace the whole pipe and only use the supertrapp, (Only if this will have a significant weight savings above just replacing the tailpipe section.) Weblinks appreciated, haven't found any good info.

1) Is this a good idea? I've never seen a Supertrapp on a Trials bike.

2) If it is a good idea, how to do it?

Thanks again.

[mr clean]

Sammy Miller Frame by <mention of this company is not permitted on Trials Central> Specialties

Yet Sammy Miller denies its existence and that they ever made one of these?

[feetupfun]

That frame in the Dirt Bike magazine test may well be a Sammy Miller frame made for a Sherpa and then modified in the US by <mention of this company is not permitted on Trials Central> Specialties to fit the TL250 motor.

[mr clean]

Aha! quoted from Sammy Miller:

The tl250 frame / tank was made from memory in a quanity of only approx 15-20 for a spsecial order which fell through so the frame and seat units were offered to USA and Australia in these quanitys. We made quite a few frame kits like this 150, 305 etc etc for specials orders which were never put into the catalogue or retail sale.

So as previous email we are unable to help with any parts because the jig for frame and tank was destoried in approx 1980 allong with the four other highboy frames.

They destroyed the Jigs???

There must be ONE of these out there, somewhere, unused! (Cheap) in a dusty corner of a warehouse taking up space....

Interesting that if this was a TL-125 it would have been very easy to find upgrade parts for the bike, frames , exhausts, engine, and everything else!

Edited August 11, 2006 by Mr Clean

[mr clean]

trials rolling chassis...

Above someone selling a Gas Gas Trials bike with engine removed. In the auction he states that a Honda or Jailing motor can be made to fit.

Anyone have any info on how to do such a project???