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Likes to race old junk.
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Discussion Starter #1 (Edited)
I thought I would share a project that I've started.
Suzuki only manufactured the T125R Stinger from '69-'71, survivors are rare.
I'm a big 2 stroke fan and always thought the Stingers were an interesting model. With the horizontal cylinders and down draft carbs, I get a 60's Japanese road racer vibe from them. I had never seen one in person, until I got the chance to trade another 2 stroke project for my Stinger. Rough as it is, its mostly complete, although its seized. I put it up on a mezzanine in my garage with some good company, and was content to just look at it until I was ready to restore it.

I've been collecting parts for several years as I ran across them, but wasn't really any closer to starting the project until recently. Jim, one of the guys who helps crew with my Bonneville stuff, has been involved with and participating in a MotoGiro event in British Columbia for the last couple of years. Held in Nakusp during early fall, it is open to 1972 and older 125cc and 250cc bikes. The event is intended to attract street legal vintage European bikes, you get awarded points for the age, how obscure of a marque it is, etc. There is a 300km (186 mile) endurance run along winding roads through the Kootenay mountains on day 1. I can not imagine wringing out a small displacement bike for hours. There will be a chase truck to pick up the mechanical DNF's.

Day 2 is a closed course competition hill climb up the paved entrance road to a winery. There is some risk involved here, its hard on equipment and bodies. I thought it would be cool to build a street legal period 1960's road racer for the 125 class. And I happened to have a suitable candidate sitting on a shelf, waiting to become something. Being Japanese, the bike will be awarded zero points for lacking a European pedigree, so if we're going to get noticed, it had better be fast. I want to use up some stuff I just have laying around and I think I can build a competitive little grenade, with a long enough fuse, to make it through the weekend.
 

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Awesome project! Thanks for sharing :cheers
 

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Likes to race old junk.
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Discussion Starter #4
I got a reproduction seat, and I really like the factory flip up seat, but I'm going to use a café solo seat.
I'm also toying with the idea of some sort of vintage fly screen or a small 1/4 café fairing, again just using up some old parts that I've managed to collect.

The Stinger is listed under Dual Purpose on Suzuki's microfiche. Its obviously a street bike, but they came with weird dirt bike handlebars. Mine will get a Clubman handlebar, that will be lower with a longer stretch to the grips. I also have some tiny vintage clip-ons but I think that might be a bit too much to ask of my back.
 

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Likes to race old junk.
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Discussion Starter #6
Every 2 stroke should have a set of expansion chambers. I scored these off ebay. Performance parts aren't common, I've bought parts from all over the world to start piecing this one together.

I also picked up a good used engine, its supposedly fresh. I recently got a Motion Pro 2 stroke leak down tester and will check the crank main seals on the "new" engine before we go too far. I'm also looking forward to inspecting the original engine, maybe its just tight from sitting and hopefully will be a good candidate for a rebuild.
 

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Likes to race old junk.
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Discussion Starter #7
Time for an update.
I've been puttering away at this project all summer.
Once I was satisfied with the dry build, I stripped the bike down and spent a lot of time cleaning. This is a budget build, I'm not going to get any thing re-chromed, what won't clean up can just get sanded and painted. Nor do I care about it being restored back to original, I'm just trying to keep it period.
Its a small bike, like 2/3 scale, its been a challenge to find accessories that are proportional.

I boreoscoped the used engine and pressure tested the crank case, no pressure drop after 10 minutes at 6psi, the crank seals are ok, I'll run it.
I scored a pair of kits on eBay and rebuilt the tiny 18mm carbs, my ultrasonic cleaner has proven to be one of my better purchases. The covers were really pitted, I filled them in with metal epoxy and they look much better.

I just spray bombed the frame with semi-gloss Tremclad black, I could have powder coated it, but I might end up welding tabs later for a steering damper. My machinist is going to fab up a pair of bronze swing arm bushings after he's done playing with the Double. I'll do what I can to try and tighten up the chassis.

I found these little drum brake scoops and made quite a mess on the work bench, drilling holes through the aluminium for the air to pass. They have little brass screens to keep the crap out. And they got new shoes and hardware.
 

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Likes to race old junk.
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Discussion Starter #8
The original wiring harness had been hacked and repaired over the years, I was fortunate to find a NOS harness and ignition switch. The system is 6 volts, which sucks at best, but you can improve them a little with extra grounds.

The new Showa rear shocks are NOS as well. I was surprised at just how much NOS spares I'd managed to collect for this project. I rebuilt the front forks using two sets to come up with one good pair and installed new seals and gaiters.

I was going to re-build the wheels with new rims and spokes but they are steel and kind of heavy. I'm going to try and source a set of aluminium rims and lace those when the time comes. I replaced a few broken spokes and cleaned up what I had. I spent an evening with my new truing stand and am happy with the results. I polished the hubs and brakes, the wheels look pretty good with the new rubber.

I'm easily distracted and brought home a mid 30's McCormick-Deering 5hp stationary engine. Of course I had to get it running before I could focus on the Stinger again. I cleaned up the magneto and now its an easy starter. It doesn't really serve any purpose other than to make some noise as it farts and pops.

I installed a new chain and sprockets.
I'd bought these cool little aluminium turn signals several years ago, figuring they would get used some day and they are perfect for this bike, I just had to convert them over to 6 volt.
The brake and clutch levers, switch housings and cables are all new.

I spent another evening wrestling the carbs, rubber Y boot and air cleaner into place...lots of cursing and the heat gun.

The bike was missing the foot peg assembly when I got it. I picked up a used one and straightened it. I'd never really sat on the bike until then. Again I knew it was a small bike, not quite ``knees around your ears mini-bike small``, but I definitely feel like an old fat guy on a moped.

I thought this vintage section would have seen a little more action. I`d like to encourage everyone to share their old junk too.

Cheers,
Scott
 

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That’s Mister Chalet To You ....
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Very neat thread to follow. More pics of your progress!

I'm easily distracted and brought home a mid 30's McCormick-Deering 5hp stationary engine. It doesn't really serve any purpose other than to make some noise as it farts and pops.
Have your neighbors asked you if you bought a Harley?
 

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Likes to race old junk.
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Discussion Starter #11
Thanks for the positive comments.

My wife gets pretty pissed when I start up the Double in the drive way, so naturally I just wait until she's not home.

She's not a fan of the turbine either, that one usually brings the neighbors out for a look. It sounds like a helicopter is warming up.
 

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Likes to race old junk.
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Discussion Starter #12
Suzuki's race colors in the 60's were blue and silver, I wanted to emulate that.

I sent my painter some pictures of old Suzuki road racers and a few modified Stingers.

He's a bit of an eccentric old hippy...go figure. I tell him what I want and then he tells me what I'm getting.
He's been a very generous sponsor over the years. I have to allow him some artistic freedom, I know when he's really into his work, that he's creative.
So I waited in anticipation...
 

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Likes to race old junk.
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Discussion Starter #13
As mentioned, I'd picked up a set of used expansion chambers off eBay. Supposedly they came off a race bike, someone went to the trouble of welding some cones together, so we'll see how they work.
If not, a I have a couple of stock systems to use.

I'd hoped to get these ceramic coated, but when I pulled off the header wrap, the welding was really ugly. They leak tested ok, but it would be best to wrap them again to cover up the chicken shit welds. I bead blasted them and drilled holes for the pyros, I want to monitor EGT's. I repacked the silencers and found some nice Akropovich springs to replace the screen door hardware that the pipes came with.
 

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Likes to race old junk.
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Discussion Starter #14
I was very pleased to pick up the painted parts.
The candy blue and metallic silver look amazing in the sun.

Its often 1 step forward and several back. I had the front end off and disassembled several times as I tried to fit the freshly painted front fender without damaging the paint.

I replaced the lens in the injector oil tank.

I've installed new cables for the speedometer, tach, throttle, front brake and clutch. Levers and switch gear are all new.
I had to run around to find the correct tiny 6 volts lights for inside the gauges.
The tail light is new.
Last night I got the carbs and injector pump set up.

Because the bike has been off the road for years and is no longer in the system, I have to get an out of province inspection done, which isn't that big of a deal, but it goes so much smoother if everything works as its supposed to.
Later I'll probably ditch the turn signals and replace the gauges with a cool rechargeable Scitsu tach that came off the Double.

This is pretty much where I'm at now. The gas tank and fairing are constantly on & off as I'm finishing up the electrical.
 

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Likes to race old junk.
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Discussion Starter #15
I've got the main harness wiring under the seat and tank sorted. The original weird dirt bike handlebars had internal wiring. The wiring from the new controls is too long, especially with the low bars that are on there now. I've got to shorten everything and tuck it up out of site.

I still need to prime the injector oil pump and bleed the lines. I'll initially fire it up on some pre-mix and then I can make sure there are no leaks at the fittings, check valves etc.

I got insurance put on it today. I hope to get it running, inspected and registered later this week...work permitting.

I'm still waiting on the correct non-resistor spark plugs. I'll also have colder and hotter range spares, plus extra main jets. I'll have to check the tune again, once I'm in the mountains.
The attrition rate is pretty high, a 2 stroke has never successfully completed the weekend without major repairs. I'll have an extra top end as well.
 

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Lovely work mate...lovely wee bike, I have some magazine articles(somewhere) featuring some restoration work on one of these, ill try and dig them out and scan them in if you wish...
 

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Discussion Starter #17
Lovely work mate...lovely wee bike, I have some magazine articles(somewhere) featuring some restoration work on one of these, ill try and dig them out and scan them in if you wish...
Thanks!
Yes, "Classic Motorcycle Mechanics" are restoring a Stinger. I've been following their build, they are still at it. I'm a fan of "Practical Sportbikes" too, we seem to get the UK magazines a month later on our shelves.
 

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Discussion Starter #18
So the moment came when I finally turned the key...and nothing...no dash lights, horn etc. It was a little humbling, this was after fitting all new wiring, carefully tracing each circuit on the schematic, cleaning connections and packing them full of die-electric grease. Where I thought it was grounding, it wasn't. The fix was as simple as sanding off some paint under the coil mounts. I wondered when was the last time that neutral light had lit up.

I cleaned the contacts on the points and had spark, I was pretty excited by this time. I decided to replace the old points with a new set, as I'm turning the adjustment screw to remove it...it isn't coming out and won't tighten up either...stripped. Ok, I'll just replace the ignition plate off the seized engine...nope. Suzuki used two different ignition / charging systems during the Stinger production run, I happen to have one of each but none of the parts are compatible. At this point, it just seems easier to pull off the left side covers, replace the rotor, stator etc from the other engine. That procedure went well, I installed new points, checked the ignition timing and set the point gap. I was rewarded with a couple of nice fat blue sparks.

I pre-mixed some gas just to be sure, I wanted to be certain that the auto-injection oil system was working first. I anticipated the worse, I expected to see gas running out of the carbs as the needles, seats and floats saw gas for the first time in years. No leaks!
I found the left side kick starter to be awkward, but she fired up. I held the oil pump full open until I could see all the air bubbles were gone in the lines. It wouldn't idle, but it ran. I wasn't too worried, I figured the plugs were saturated in oil. Although the door was open, I quickly filled the garage up with blue smoke and got an instant headache from the fumes. However, I was happy...I smelled like 2 stroke!

I fired it up again the next day and took it around the block. There was a popping noise when I revved it up and I could see smoke escaping from the head gaskets. I pulled the heads off, saw that the bores were in good shape and cleaned everything up. I checked for straightness and reassembled with new gaskets. It started on first kick and idled once warmed up. I was anxious to take it for a good run.
And then it rained every day for a week.

I did manage to finish installing the EGT gauge while I waited. I don't mind driving in the rain if I'm caught in it, I just have a problem with heading out in it on purpose. I also wanted to get some pictures of the bike while it was still clean, it will never look as good as it does right now.
 

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Likes to race old junk.
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Discussion Starter #19
I decided to personalize the bike a little.
After the Motogiro, it will likely get put back up on the shelf and I'll continue on with other projects.

Its way too nice now to ever take to Bonneville for use as a cool pit bike, the salt will ruin it, just as its wrecked all my other shit. If I ever run at El Mirage again, I would certainly take it there.

Turple Bros in Red Deer, my local supporting Suzuki dealer, have been sponsoring me and my adventures for over 15 years.

The seat still tilts back to access fuses etc along with the tool kit that sits under the gas tank. I'm sure I'll be changing plugs on the side of the road at least once.

The bike works great. Small displacement or not, there's a rewarding feeling when a 2 stroke comes on the pipe at 6 grand. The brakes are surprisingly good...considering.

I spent yesterday afternoon bombing around town with a big smile. I ran it out to a friend's acreage last night and drove home in the dark with a feeble 6 volt yellow headlight.

I've seen 60mph on the speedo and there's more there. I'll take it easy until its survived the endurance run on Saturday. I'll thrash it on Sunday during the closed course event. I need to check the plugs again and adjust the chain, but otherwise its ready to go on the trailer. I'll leave for the mountains tomorrow evening.

Cheers,
Scott
 

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