My 50cc 2 stroke Minibikes - Honda NSR50 and Yamaha TZM50R

[dom10a]

Back in the 80s and 90s, Honda, Yamaha, and Suzuki made some mad minibikes. These ones are 3/4 size versions of their bigger brethren, the Honda NSR250 and Yamaha TZR250. 

I imported the Honda NSR50. That bike was complete and original and just needed new fluids, tyres, battery. 
The TZM50R was a restoration project. I'll post up some more pics of the work done to that bike.

Both bikes are surprisingly quick. 

The bikes are true mini versions of the originals and have all the features of the full size bikes. 6 speed gearbox, water cooled engine, electric start (on the Yammy), twin piston front calipers.

Both are road legal and registered.  

[dom10a]

Restoration of the TZM50R. The bike had been raced in Japan and was missing a lot of the original parts such as lights, wiring loom, ECU, original exhaust, oil metering pump (converted to run premix). Stuff like carburettor jetting had been changed and front and rear sprockets were a country mile from stock. I'm still ironing out the top end performance as the bike bogs down at speed under load. I'd say the bike is now 95% original. The only non original bits are the rear coilover shock, which I like and will keep on the bike, the lack of oil metering pump (if I ever find one I will put it back on), and the fully floating front disc, which was one of my modifications.





Collecting the bike. Fits in the back of the pickup truck nicely!

[dom10a]

Fitted a master cylinder rebuild kit and repainted it and fitted new lever and stainless screws.



Pad anti squeal bracket had split.






Titanium pistins, pins, and bolts.



Old exhaust was beyond saving. Holes everywhere. Have since tracked down an original exhaust for it and removed the wasps nest from within!The NR Magic screamer exhaust looks ace though.






Tyres were gone. The rubber was like plastic. 



Wheels were powdercoated and new tyres fitted. Also fitted floating front discs and titanium fasteners.



Forks were too pitted to get through an MOT so were rechromed. They were also found to be bent so were straightened. 















It has the smallest starter motor I've seen!




Fuel tank had a couple of chips and dents so was resprayed by TJC Designs in Bristol. They did an amazing job.

Before:



After:




Handlebars were bent and had to be machined off and new tubes tig welded on. 



The bike was raced so the original wiring loom had been binned. The ECU was also removed. All that was left was the cutoff switch and the coil. Luckily I managed to find a good original wiring loom and ECU from Japan.  




Speedo was missing but managed to find one from Japan. I had the foam anti vibration pad replicated as they are no longer available. 







Inlet to water pump! 






Thermostat had seen better days. 

[dom10a]

Collecting the NSR50 from the docks. The shipping agent in Japan did an amazing job of crating it up.

[dom10a]

[turbom]

I remember the local Suzuki dealer having one of these size bikes in the mid to late 80"s
did not know what it was.

[dom10a]

May 23, 2020 12:06:43 GMT turbom said:

I remember the local Suzuki dealer having one of these size bikes in the mid to late 80"s
did not know what it was.

It would've been the Suzuki RB50.

[zeberdee]

You’ve done s good job on them !!

Always wanted one , but at 6’5 , it’d just be an ornament .

👍

[dom10a]

May 23, 2020 13:30:30 GMT zeberdee said:

You’ve done s good job on them !!

Always wanted one , but at 6’5 , it’d just be an ornament .

👍

Thanks. Yeah I'm 6ft2 and can just about ride them. I find it helps to squat like Gollum first to get limbered up   

[TessierAshpool]

These are great, such a quality design compared to the Mecatecno I've been working on recently. Didn't even know these existed, didn't really think to look at what Japan had built (other than the Honda monkey bikes)

[dodgerover]

I remember these, always thought these would be great fun

[merryck]

Amazing! Never even knew these were a thing!

[dodgerover]

I remember fancying a Kawasaki KSR80 that came in as a part exchange, it looked very much like a factory super Moto kx80.
Sadly I never managed a test ride which is probably a good thing because I have no idea how parts would have been found at that time. The importers still came round with a paper photo album of the bikes they had on the way over so you could order them!

[danny81]

Great bikes cant beat a small bore 2 stroke !

[Tazzy]

bookmarked

[goldnrust]

How cool is that! It's great how much like the 250s they look, especially if that shot of the two of them together in the first post. The proportions are just right. Look like they've found a good home, lovely detail on that restoration, they look better than new.

The NSR looks especially cool. An MC28e is in my dream bike garage for sure!

It's a shame that you can't buy smaller capacity bikes that are 'proper' any more. My RGV250 was great, and so was my CBR400rr and VFR400, and they were full race bikes as aggressive, challenging and well specced as the big 1000cc stuff. Nowadays it seems anything smaller than 600cc is a 'beginner bike' and comes with budget suspension and easy safe riding position.

[lebowski]

Wow! Those are awesome. What were they made for? I presume they aren't restricted at all like a regular 50cc learner bike? I was going to say you must be a midget but you're the same height as me. I once had a little go on my friends VFR400 and even that felt tiny and uncomfortable to me.

What are they worth approximately?

[waynedear]

Exceptional work there, I do prefer the style of the knackered exhaust and love the overkill of a twin piston front caliper 😁

[dom10a]

May 24, 2020 9:58:18 GMT goldnrust said:

How cool is that! It's great how much like the 250s they look, especially if that shot of the two of them together in the first post. The proportions are just right. Look like they've found a good home, lovely detail on that restoration, they look better than new.

The NSR looks especially cool. An MC28e is in my dream bike garage for sure!

It's a shame that you can't buy smaller capacity bikes that are 'proper' any more. My RGV250 was great, and so was my CBR400rr and VFR400, and they were full race bikes as aggressive, challenging and well specced as the big 1000cc stuff. Nowadays it seems anything smaller than 600cc is a 'beginner bike' and comes with budget suspension and easy safe riding position.

Yes they did a great job on making them true mini versions of the 250cc bikes. Thanks for the kind words, I really enjoyed working on them. 

Modern stuff does seem to be getting pretty crazy with the engine sizes and weights. 

This is a cool image from some promotional shoot of the some of the mini bikes available at the time. Honda built them for quite a few years.

Someone called them Motor Bonsai once. I like that term.

[dom10a]

May 24, 2020 11:19:28 GMT lebowski said:

Wow! Those are awesome. What were they made for? I presume they aren't restricted at all like a regular 50cc learner bike? I was going to say you must be a midget but you're the same height as me. I once had a little go on my friends VFR400 and even that felt tiny and uncomfortable to me.

What are they worth approximately?

Thanks mate. I think they were made as tribute bikes to celebrate racing successes of the full sized bikes, but presumably were also built against some "gentleman's agreement" type rules as the sizes, weights, power figures of the Honda and Yamaha in particular are almost identical. I imagine this was so kids (and overgrown kids like myself) could race them on small circuits. 

The values vary massively. Raced ones missing lots of the original bits can be had for a grand or less but you will spend thousands on parts if you want to restore it properly. I wasn't prepared for how expensive parts are. A decent mostly original Yamaha TZM50R would be 3-4 grand. There is one currently for sale in the UK. Looks very original and could be made mint with not much work.

suprememotos.com/yamaha/88557-yamaha-tzm50-gag-nsr50-ysr-era.html

A perfect one with very low miles could be more. Original fairings go for crazy money on the Japanese auction sites as you can't get replacements any more. 

A mint Honda NSR50 in arguably the nicest livery came up for sale at auction in 2013 and sold for $8050 (£6500 at todays exchange rate).

rmsothebys.com/en/auctions/bw13/the-bruce-weiner-microcar-museum/lots/r264-2004-honda-nsr50-minibike/286276

My NSR50 cost me around £5000 all in once shipping and taxes paid. Silly money really but they are collectible as they're so rare and look the part in any collection and are huge fun to ride.