My new 1978 SR500

DogBunny

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Bought this 1978 SR500 with 11K miles for $2,000 a few years ago, and finally got it running several days ago. All it needed was a tank and carb cleaning to run. And, I replaced the crystalized master cylinder with a cheap Chinese M/C, and I replaced the flasher relay to make it pass inspection.
Came with a tremendous aftermarket Mikuni TM36-69 pumper carb, what I think is a big bore header, and K&N air filter, all of which adds up to awesome.
Hot or cold, it starts exceptionally easy, unlike every XT500 I've ever ridden. CDI-Magneto ignition, with no points to adjust, and the battery has been replaced with a capacitor.
All it needs now is a deep clean and polish, which will probably never happen unless I decide to sell it.
My only two complaints are that it should have come with wire spoke wheels, like some of the European models and the XT/TT500. And, the black color. I wish it had something more along the lines of the 70-73 XS650 color schemes.

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I've always like the SR500. Never ridden one, but it is on my watch list if one would pop up locally. Curious, being that the SR and XS shared some similar parts, does anyone know if XS wire wheels could be adapted to an SR? I agree it would look much better with them.
 
All it needs now is a deep clean and polish, which will probably never happen unless I decide to sell it.

Since the engine sides are relatively flat it could be done with some Autosol and a hand held drilling machine + polishing wheel
fairly quickly
If one wish so
 
I've always like the SR500. Never ridden one, but it is on my watch list if one would pop up locally. Curious, being that the SR and XS shared some similar parts, does anyone know if XS wire wheels could be adapted to an SR? I agree it would look much better with them.
Don't know about XS wheels, but I would think that XT500 or TT500 wire spoke wheels might be a direct swap, and they sell used relatively cheaply. However, then you would have a drum front brake, better-looking, but poorer stopping. On the plus side, the XT500 rear wheel is cush drive.
Also, just checked, the XT/TT500 front wheel is 21", the SR500 is 19". That actually only equates to an extra 1" in diameter as measured with a tape, due to different tire fatness.
Since the engine sides are relatively flat it could be done with some Autosol and a hand held drilling machine + polishing wheel
fairly quickly
If one wish so
Thanks, but one does not wish so. I have too many bikes to keep them all looking good.
View attachment 249352

Some of them did come with wire spokes. Drum brake complicates the swap.
That's a European model. You can tell by the grab bar behind the seat, and the lack of the rear seat cowl like in my pics.
The U.S. SR500 was mag only.
 
Don't know about XS wheels, but I would think that XT500 or TT500 wire spoke wheels might be a direct swap, and they sell used relatively cheaply. However, then you would have a drum front brake, better-looking, but poorer stopping. On the plus side, the XT500 rear wheel is cush drive.
Also, just checked, the XT/TT500 front wheel is 21", the SR500 is 19". That actually only equates to an extra 1" in diameter as measured with a tape, due to different tire fatness.

Thanks, but one does not wish so. I have too many bikes to keep them all looking good.

That's a European model. You can tell by the grab bar behind the seat, and the lack of the rear seat cowl like in my pics.
The U.S. SR500 was mag only.
How about SR400? I’m sure you can buy brand new wheels if you wanted to. Cast wheels work great!
 
Thats a beauty you have there....they've really started fetching good prices these days, getting harder to find too.

You cant really swap wheels for spokes (except for an XT500 wheel) if you want the transmission to last. The rear mag wheel has a cush hub built into it to soften the blows of that big thumper on pavement. 👍

I have the dirt version...love that big thumper motor. The 78 TT500 I had in High School late 70's/early 80's was my do it all bike, flat track, motocross, hill climb...rode the wheels off that bike!

In a fit of nostalgia I had to get another one all these years later.

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Bought this 1978 SR500 with 11K miles for $2,000 a few years ago

That is so cool! Like you , I also had an XT500 ( in fact I think we both had the same year, that brown model ) , I had done some work to uncork the motor , with a Super Trapp pipe, a big K+N air filter and bumped up the jetting. And was surprised at how much more power was available from that motor. It made for a very flickable street bike. I always thought it would be fun to have that motor in a dedicated street bike like the SR.
 
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I've always like the SR500. Never ridden one, but it is on my watch list if one would pop up locally. Curious, being that the SR and XS shared some similar parts, does anyone know if XS wire wheels could be adapted to an SR? I agree it would look much better with them.
I'd say yes... prolly relatively easily.
 
I've always like the SR500. Never ridden one, but it is on my watch list if one would pop up locally. Curious, being that the SR and XS shared some similar parts, does anyone know if XS wire wheels could be adapted to an SR? I agree it would look much better with them.
You'd want to use a rear wheel from an XT500.

The mag wheel has a cush hub so the transmission will survive the pulses of that big single on pavement.
 
View attachment 249339
Bought this 1978 SR500 with 11K miles for $2,000 a few years ago, and finally got it running several days ago. All it needed was a tank and carb cleaning to run. And, I replaced the crystalized master cylinder with a cheap Chinese M/C, and I replaced the flasher relay to make it pass inspection.
Came with a tremendous aftermarket Mikuni TM36-69 pumper carb, what I think is a big bore header, and K&N air filter, all of which adds up to awesome.
Hot or cold, it starts exceptionally easy, unlike every XT500 I've ever ridden. CDI-Magneto ignition, with no points to adjust, and the battery has been replaced with a capacitor.
All it needs now is a deep clean and polish, which will probably never happen unless I decide to sell it.
My only two complaints are that it should have come with wire spoke wheels, like some of the European models and the XT/TT500. And, the black color. I wish it had something more along the lines of the 70-73 XS650 color schemes.

View attachment 249340
View attachment 249341
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View attachment 249343
Mighty fine!😁👍
 
Thats a beauty you have there....they've really started fetching good prices these days, getting harder to find too.

You cant really swap wheels for spokes if you want the transmission to last. The rear mag wheel has a cush hub built into it to soften the blows of that big thumper on pavement. 👍

I have the dirt version...love that big thumper motor. The 78 TT500 I had in High School late 70's/early 80's was my do it all bike, flat track, motocross, hill climb...rode the wheels off that bike!

In a fit of nostalgia I had to get another one all these years later.

View attachment 249353
Nice!

That is so cool! Like you , I also had an XT500 ( in fact I think we both had the same year, that brown model ) , I had done some work to uncork the motor , with a hipipe, a big K+N air filter and bumped up the jetting. And was surprised at how much more power was available from that motor. It made for a very flickable street bike. I always thought it would be fun to have that motor in a dedicated street bike like the SR.
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Yes, here's mine.
I'm embarrassed to admit this, but this bike has been sitting for a few years do to a relatively simple fix that I've had no inspiration to do. However, now that I've reacquainted myself with the XT/TT/SR500 family, I guess I'll finally address it.

Yes, the new SR500 is very flickable and a torque monster. Grip the bars firmly before take-off. Weighs considerably less than an XS650. Added bonus, it's incredibly easy to get on the center stand.

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This is the XT500 I built that was in the Handbuilt Show several years ago. The whole front end, wheel, forks, triple, are from an XS650.
 
You'd want to use a rear wheel from an XT500.

The mag wheel has a cush hub so the transmission will survive the pulses of that big single on pavement.
The 650 front wheel is a direct swap. For the rear, you want an XT500 wheel with the cush drive. The TT500 doesn't have the cush drive.
Okay, maybe I will look into it. Maybe. I have 650 fronts and XT rears already.
 
Oh, the nostalgia. Bought one new in 1979. I was leaving paid employment to go to uni as a mature student, so I used the pension money my employer paid back to me to buy a new bike to last the duration. Well, at 22 retirement was a long way off so . . .

Would have been the European model - wire wheels, disc front, drum rear. Loved the light weight, narrow, good handling, flickable as said above. Perhaps rashly, once it was run in, took it to Dixon Racing in Godalming for a tuning job - hi-comp piston, 9:1 went up to 10.7:1, still had lead in our petrol then, Kenny Harman hi-lift drag-race camshaft - IIRC correctly the exhaust valve duration was 420°, stiff valve springs, etc. Sure went like stink.

But didn't last too well. The CDI unit gave up - bike was 15 months old and other people had the same problem so I tried to get Yam to replace it FOC but they wrote back the guarantee is strictly One Year. For a pore student, that was a huge hit. Then third gear broke - led to my first ever engine rebuild. Then the cam followers wore out - them stiff springs I guess? Then, well a catalogue of failures really.

Years later, gave the SR to me nephew who had a decidedly hairy moment on the M25 London orbital motorway - he stepped off it as it went under an artic. Thankfully, he survived with minor injuries but that was the last of that bike.
 
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