1978 custom resto, its been a while, but i am back.

[bbrown]

Was on this site a few years back fixing and restoring old 650's, got lots of help and ideas off the great people here.

I just recently picked up a 1978 Yamaha 650, 1 owner, 15 K miles, runs.
Needs a lot of love its been sitting for 15 years in a barn, with the only in that time was an midnight joyride by his neighbors kids, returned the next morn, with a few road rash boo boos!

I also have a few 650 parts bikes, 83 heritage that was dumped hard but engine and a lot of other parts are really good shape, and a 74XS that runs but no papers and a 78XS thats had all good parts stripped from it.
I have a few other old bikes that i collected cause they have some cool parts that (hopefully) i can custom fit.

Not an expert by any means but not afraid to try something i have not done.

Pics to come soon.
P.S. Good to be back, its been to long

 

[bbrown]

1978 650 RSide

• bbrown
• Aug 7, 2020

1978 650, best wheels on the 650's in my opinion.

Ok, Here is the promised pics.
Gonna start a post in right thread and try to update as much as possible.

Plan roughly is:
Mechanically sound running bike, like most of original look, like the patina aged look, but clean.
Has a lot of old parts to swap (from 650's and other models).
Lower profile seat, get rid of airbox but keep side plates.
Change out handle bars, lights and gauges.
Also do the usual 650 upgrades, steering bearing, swing arm, clutch, etc.

 

[bbrown]

So it begins!

 

[bbrown]

Some misc parts i got I was thinking about.

 

[bbrown]

Brake rez 74 kaw 440
horn 1961 Aermacchi harley davidson
Tombstone off a HD
Fog light off ?
Misc bars and grips (lots)

 

[Jim]

Gonna start a post in right thread and try to update as much as possible.

You're in the Garage... perfect place for a build thread. Just keep it going here. You can change the title to anything you want.
Looks like you're off to a good start. Watching.

 

[Boog]

Hello BBrown and welcome back from Virginia

 

[5twins]

You have a very good model to work with but I'll admit to being rather partial to it. I've had my '78 Standard for nearly 15 years now and it's been a wonderful bike .....

I latched onto a Special a couple years back and am slowly trying to make it as good as the '78, but not quite there yet.

The '78 has the notorious type D cam chain tensioner. You'll be wanting to upgrade that to a type E.

 

[bbrown]

I have followed and admired your work since i last was on.

You have a very good model to work with but I'll admit to being rather partial to it. I've had my '78 Standard for nearly 15 years now and it's been a wonderful bike .....

I latched onto a Special a couple years back and am slowly trying to make it as good as the '78, but not quite there yet.

The '78 has the notorious type D cam chain tensioner. You'll be wanting to upgrade that to a type E.

 

[bbrown]

Ordered a cleaner.
So do i rebuild the 38's or the 34's?
From what i remember the 38's are a little more responsive and the 34's are easier to tune and better mileage, is this correct?

 

[bbrown]

Also any old schools know the name of this part? I call it a suicide cruise control! lol
its off a 74 KZ 440 and might make it on the bike, i think its looks cool.

 

[5twins]

On the carbs, it's probably the opposite, although I don't think the 34's are any more responsive. The '78-'79 BS38s are about the best of those carbs, last set used and most refined. I think I'd stick with them if possible.

I have the 34's on my '83 and while they work fine, I don't think I'd put them on another 650 if it already had good working 38's. Honestly, I don't notice much difference, if any, in the performance between the two. The 34's do have a few advantages though. They're lighter, a bit more modern and refined, and the intake manifolds for them are more readily available and usually cheaper than 38 manifolds. Also, the plastic floats used from '81 on are very nice. They're a solid foam so can't spring leaks which means technically, they should never go bad. Oh, and the Viton rubber tipped float needles are also very nice.

 

[bbrown]

On the carbs, it's probably the opposite, although I don't think the 34's are any more responsive. The '78-'79 BS38s are about the best of those carbs, last set used and most refined. I think I'd stick with them if possible.

I have the 34's on my '83 and while they work fine, I don't think I'd put them on another 650 if it already had good working 38's. Honestly, I don't notice much difference, if any, in the performance between the two. The 34's do have a few advantages though. They're lighter, a bit more modern and refined, and the intake manifolds for them are more readily available and usually cheaper than 38 manifolds. Also, the plastic floats used from '81 on are very nice. They're a solid foam so can't spring leaks which means technically, they should never go bad. Oh, and the Viton rubber tipped float needles are also very nice.

Thank you 5twins, you have probably forgot more than I know!