Topic: 1970 CB750 K0 Tracy in my shop

[MoMo]

Just got a Tracy 750 K0 brought into my shop for repairs and thought you all might enjoy some photos.  Owner picked it up for 1750, he got it running but it would not idle below 3000(check the photo of the throttle cables).  Bike had been sitting in a warehouse for the past 10 years-chrome is excellent and paint is gorgeous. Headlight if fugly and wiring is horrendous.
 
If anyone has a set of fork ears, headlight and shell, he may be interested.  I have fork ears, headlight and shell from a 1974 Yamaha that I can make work.  Sacrilegious?

Also, anyone know what header is on the bike?, Jardine?

I'll keep updates posted.  Not a full rebuild, just get running right and wire correctly,,  Larry

[754]

 Triple A header, been looking for one for decades, so is MCRider..
 usually rot off just behind the collector..  but the headpipes are important..

[Zaipai]

Nice, you are right that headlight is awful. What is with that exhaust, is it a good one? Its such a shame when some one leaves a bike sitting for 10 years. At least its seeing the light of day now!

.: Scott :.

[MoMo]

thanks for the info on the header and it is in very good condition save for one bit of road rash. The muffler is also in very good condition. The header looks like a bunch of spaghetti twisted around.  Also, I think there may be a big bore kit as it looks like someone tried porting the intakes(not very well by the way), plus there is the usual telltale conversion to all stainless steel allen heads.  Thanks, Larry

[beelsamin]

Interesting...I had an aftermarket front fender exactly like the one pictured on my '72 Suzuki GT750, bought it in'74 after a car rear ended me into the car stopped in front of me...don't recall who made it tho'

[sandman]

Boy, that header is wild- never saw one on any 750 around these parts.

I clearly remember the magazine ads for those Tracy body kits, though. They've aged surprisingly well visually, at least. I don't know about cracks and build quality, hopefully they don't all leak- I guess you can answer that one...

[MCRider]

thanks for the info on the header and it is in very good condition save for one bit of road rash. The muffler is also in very good condition. The header looks like a bunch of spaghetti twisted around.  Also, I think there may be a big bore kit as it looks like someone tried porting the intakes(not very well by the way), plus there is the usual telltale conversion to all stainless steel allen heads.  Thanks, Larry

AS 754 mentioned...

You can see my TripleA header on a K1 in my avatar. That bike has a 2 piece Tracy tank and double seat combo. Figured I'd be taking the girls for a ride, never happened.   836 kit (early made from CB350 pistons) and a head ported by a Yoshimura employee.

Photo taken in Feb 1972. Each pipe is individual. You have to mount them all up and put into collector. That bike was stolen shortly after. Came across the header again in 1974, sold it in 1985. Never seen one again...till now.

Muy buenos recuerdos   

[Ricky_Racer]

754 and McRider... I have a set of the TripleA headers to use as a pattern. They are definately complicated, but there is a slim chance that I might be able to reproduce them if there's sufficient demand. Obviously initial tooling/setup costs is the issue, with production costs following closely behind.

Do you think there would be sufficient demand at a popular price point?  If you think so, I'll pursue the matter further.  Otherwise, they're going on my late model Tracy build. Thanks. RR

[754]

 If everyone could have one, I may not want it anymore..

 still trying to buy my riding buddies 71 with that header and rotted off meg, he bought the bike and pipe new.

 I am really interested in high pipes to get better ground clearance.. will have to build something soon..

[Ricky_Racer]

Thanks, Frank. I'm too old with too many projects to do to spend resources on iffy ideas. Looks like this one is going to be a low-priority project; I guess I'll get around to it if I ever happen to get around to it. Other challenges are easier.  L8R. RR

[MCRider]

Thanks, Frank. I'm too old with too many projects to do to spend resources on iffy ideas. Looks like this one is going to be a low-priority project; I guess I'll get around to it if I ever happen to get around to it. Other challenges are easier.  L8R. RR

Yeah, I've got pipes for my two projects. Marshall Deep Tone for Phaedrus, and a hand belt Bol D'ors replica for Free Bird.  I'm just glad to see the TripleA pipe is still around somewhere. They seem to be attracted to Tracy bodywork. 

If I live long enough to do a 3rd CB750, I'd be in the market.

[MoMo]

Out in the shop and cleaned the carbs last night, very clean for a bike that sat for 10 years-must have been drained. Midrange jets just a bit coated.

To the question about the tank-the owner had gas in it and it did not leak, so I'm hoping it will not need to be coated.  Has anyone coated a fiberglass tank if it needs to be done? The tank looks like it couldn't hold more than a gallon and a half, and at roughly 35mpg that means very frequent gas stops!

Build year is 11/69, frame #1012951 and engine #1013808.

[MoMo]

On further inspection of the carbs I found two holes in one float, so there must have been gas/water during the 10 year span. The area is pretty thin, I think any repair would add too much weight .  Any ideas? Anyone have a float for the old K0 4 cable carbs?

[Hinomaru]

On further inspection of the carbs I found two holes in one float, so there must have been gas/water during the 10 year span. The area is pretty thin, I think any repair would add too much weight .  Any ideas? Anyone have a float for the old K0 4 cable carbs?

If you want new KO brass floats, Yamiya (Japan) has them:

http://www.yamiya750e.com/index.php?main_page=product_info&cPath=27&products_id=147

[754]

I am pretty sure floats work by displacemt and tang setting, not weight..
 They were soldered when they were new, were they not?

[MRieck]

I am pretty sure floats work by displacemt and tang setting, not weight..
 They were soldered when they were new, were they not?

I'd worry about a porous condition Frank....and that is for all the floats

[seaweb11]

Out in the shop and cleaned the carbs last night, very clean for a bike that sat for 10 years-must have been drained. Midrange jets just a bit coated.

To the question about the tank-the owner had gas in it and it did not leak, so I'm hoping it will not need to be coated.  Has anyone coated a fiberglass tank if it needs to be done? The tank looks like it couldn't hold more than a gallon and a half, and at roughly 35mpg that means very frequent gas stops!

Build year is 11/69, frame #1012951 and engine #1013808.

I used Por-15 for my Tracy and it is holding up just fine.
It did not leak when I got the bike, I just wanted to make sure.
http://forums.sohc4.net/index.php?topic=17831.msg536889#msg536889

P.S. I just drilled out the fuel tube that got clogged

and yes, that tank will not take you far.

[spot45]

Soldering the floats will mess with the floats mass.  They won't work right best to go buy the floats from Yamaiya.

[754]

I did not mean wrap solder around and glue it on..
 I was thinking you can solder a thin layer of shim stock patch.. as an alternative to new floats. From Yam.. How much are they anyway?? I am guessing 200 bux? It soes not matter what they look like just need to maintain fuel at a certain level..

 I mean, you may find used but not in a week...meanwhile you can get it running.. who knows the owner may want to change to linkage carbs in a few months

[singedebile]

754 and McRider... I have a set of the TripleA headers to use as a pattern. They are definately complicated, but there is a slim chance that I might be able to reproduce them if there's sufficient demand. Obviously initial tooling/setup costs is the issue, with production costs following closely behind.

Do you think there would be sufficient demand at a popular price point?  If you think so, I'll pursue the matter further.  Otherwise, they're going on my late model Tracy build. Thanks. RR

Was anything similar ever made for the 500/550? (maybe by another company) really kinda like the look of them!

[MCRider]

I did not mean wrap solder around and glue it on..
 I was thinking you can solder a thin layer of shim stock patch.. as an alternative to new floats. From Yam.. How much are they anyway?? I am guessing 200 bux? It soes not matter what they look like just need to maintain fuel at a certain level..

 I mean, you may find used but not in a week...meanwhile you can get it running.. who knows the owner may want to change to linkage carbs in a few months

754: The Yamiya brass K0 floats are $46 ea. todays exchange rate. Plus shipping probably $18+/-. Borderline choice between a repair and a brand new float, in my mind.

[MoMo]

After I wrote about adding weight by trying to repair the float I realized that it works by displacement  and I believe any weight added would have minimal effect.  Thanks for the info about the Yamiya float, if my repair doesn't work, that will be the direction. I also have a set of floats from a 77 CB750 that I think I could make work

[ekpent]

I have swapped out brass floats in my K1 carbs with plastic floats 76 or older with no issues.Aren't 77 totally different carbs  never had one that new 

[MoMo]

Yes, they are totally different-the ones with the accelerator pump but it seems that the float will fit in the older carbs.  Not sure if I'll spend too much time trying to make that work or have the custome buy from Yamiya if my repair fails.  Thanks, Larry

[754]

I dont know if solder will fill a gap without blobbing.. but you can get some thinbrass shim stock..10 thou or under, and make a small patch strip. It will cut with scissors..