Topic: Speed Pony - 550 race bike recreation

[scunny]

subscribed. 

[Tintop]

subscribed. 

Welcome aboard, should be a fun trip.

[Tintop]

A quick update on some of the parts used.

Received an email from Scott McKay who work on the bike.   According to Scott not only was the front hub TZ, the entire front wheel was from a TZ750D, including the disks.  The master cylinder was also from a TZ750D, along with the shock.  This information settles the question of which shock / swingarm.  The recreation will use the TZ750 units (swingarm like the one above).  TZ750D disks are available, but I am very reluctant to trust my safety, or anyone else's to 35+ year old brittle magnesium.  At this point will stay with using CB750 hubs.

He also mentions that the front calipers were Yamaha.  However, this will take further checking as the mounting system used was clearly Honda.  He did confirm that the front end was 'modified stock parts'; which I know were CB750.

The one blank I had, carbs, was answered as well.  Seems though they tried Mikuni Smoothbores ('mixed results'), the bike performed best with CB550 carbs!   From the pictures these would appear to be possibly 550F's.  No information though on how they were setup / modified.

[bwaller]

The fellow I mentioned to you that raced that 592 (before reaming it up to 685) claimed he liked a set of bored CB750 carbs best with that engine. If they did use 500/550 carbs they must have "breathed on them" quite a bit. I can't see how they can be bored big enough to feed a 61mm bore for racing though?? Maybe they might work at (Nelson) Shannonville.

Did he mention what the issues were with the Mikunis? I wonder again if it was a small tight track where they didn't like them. 

[Tintop]

I just as suprised as you Brent.  Have asked the same questions, and am waiting for a reply.

Most of the guys I have spoken to racing 550's in VRRA are running 750 carbs.  As you say, they must have been 'breathed on'.   Given that my 1275 Spitfire Solo motor ran 28 chokes, and the race 1600 TC 32's in their Webers...    As you say, these probably worked well at Shannonville, gave it a very strong midrange, but restricted WOT potential.  That kind of power would also work at Mosport, everywhere but the back straight.

[Tintop]

Brent - rec'd this from Scott McKay in answer to my carb question:

"The smooth bores never worked, I believe we tried to sort them out and gave up.
No, we never used 750 carbs to my knowledge.
The stock 550 carbs we had used previously in numerous streetbike applications, thus knew our way around them pretty well.
Jeez, I wish I had the notes from way-back-when.... "  (So do I.. )

Guess it's time to start looking for a set of early 550 carbs for the build.   Hondaman gives some details about modifying stock carbs in his book.  Will have to re-read that section.  Time to buy that Dremel.

[HedNut]

OH WOW...this is good stuff!!  I'm hooked!

[Tintop]

OH WOW...this is good stuff!!  I'm hooked!

I got hooked 3 years ago when I 1st heard about this bike.  Take a seat HedNut, should be a fun ride.

[bwaller]

I've got a bunch of carbs, I'll get back to you.

[Syscrush]

The one blank I had, carbs, was answered as well.  Seems though they tried Mikuni Smoothbores ('mixed results'), the bike performed best with CB550 carbs!   From the pictures these would appear to be possibly 550F's.  No information though on how they were setup / modified.

Are we talking about CV carbs? 

[Tintop]

I've got a bunch of carbs, I'll get back to you.

Thanks Brent - figured you would probably have something. 

Besides, I know a guy with a racing CB550, that might need some extra speed for those young guys.

[Tintop]

The one blank I had, carbs, was answered as well.  Seems though they tried Mikuni Smoothbores ('mixed results'), the bike performed best with CB550 carbs!   From the pictures these would appear to be possibly 550F's.  No information though on how they were setup / modified.

Are we talking about CV carbs? 

Thank for the interest Syscrush - in a word no, they were Mikuni Smoothbores, probably VM29's (?).  The most likely probability is that the Keihins used were probably 069A's for an F bike.  Still trying to nail that down.

[Tintop]

In my search for information on the 550, I have also been tracking down additional info on Robbie Meiklejohn's 750 based bike.

Rec'd the following from Mike Crompton today:

"....I built the bike for Robbie and fabricated all the parts to fit as well as all the engines. Robbies brother Gordon rode it in amateur and Robbie ran it in pro. We would change the bars between clipons to high bars for Robbie. One thing to watch in the new fab is the chain clearance as the original swing arm had to be modified as the chain wanted to run through the shock structure. I remember all the headaches of fabricating an oil tank to fit around the upper swing arm as I wanted a large volume tank because of the heat the engine was generating because of it's  size...."

So that answers bwaller's question - Gordon Meiklejohn did race the 750 version.

[Aladinsane07]

Very much subscribed 

[bwaller]

Sorry Brian, I must have sold most of them, only one set of 627's and I should keep those.

Shouldn't be a problem finding.

Interesting to hear Crompton was involved too...hell that's a who's who of Canadian talent, Curtis, Meiklejohn, and now Mike Crompton. Too bad he hadn't been involved in the 500 stuff.

[Tintop]

Sorry Brian, I must have sold most of them, only one set of 627's and I should keep those.

Shouldn't be a problem finding.

Interesting to hear Crompton was involved too...hell that's a who's who of Canadian talent, Curtis, Meiklejohn, and now Mike Crompton. Too bad he hadn't been involved in the 500 stuff.

Thanks for checking Brent.  As you say they shouldn't be a problem to source; and there's lot's to do before they will be needed.  The PD's on my cafe were always meant to be a test bed for applying my SU / Weber knowledge.  Now there will be a real purpose.

Yeah the who's / who list keeps growing.   The 550 seems to have been pretty much a privateer effort (through Ontario Honda).  It was also an 'in house' effort so to speak, what with the involvement of Rick Andrews & Scott.  I'm sure that's were the TZ750D parts came from, as I remember standing in the showroom staring at one in awe.   As Scott McKay put it - "....at the time it was built we were young, stupid, invincible and didn't know we couldn't so we did."  He also credits Murry Brown the owner with "...gave us the privilege of trying, sometimes succeeding and sometimes failing."  Must have been a great, and exciting place to work.

[Tintop]

Received some more information on the frame's early history.  So a correction to the number of frames built, & who owned what / when.

1st the # built.
According to Denis there were 4 frames built (not 6 as I had previously thought).  Two went to Ontario (he was in Vancouver at the time), one to Winnipeg (?), and one stayed in BC.  It became a street bike, that got a 750 with a Piper prototype 8 valve head.

The frame for this bike was one of the two sent to Ontario in 1973.  It was not however 'Robbie's 2nd frame', as I have now found out.

from Mike Crompton:
 " The frame that was used for the 500 was purchased by Rick Andrews of Ontario Honda with the intention of putting a 750 in it. It was the mate to Robbies."

from Scott McKay in answer to my questions:
When did you guys build the bike? - "I believe the bike was built over the winter of 78/79."
Was it Robbie Meiklejohn's 2nd frame that was used? - "Robby never owned a second frame, Dennis Curtis built it (as I recall) at Rick Andrews' request."

That would seem to establish the when & for whom.  Still trying to find out how Wayne McLelland end up building it at Ontario Honda. Also looking to track down more photos.  I'm also working on gathering more of the bike's later history.

[bwaller]

It's 10:15 why are you not at the track?    Good pics by the way.

I know what the comeback to that one is, but I just couldn't get away.

Sounds like you have released the information hounds, hopefully all your answers are forthcoming. I remember hearing about that 16 valve Piper CB750 but had left Van. before that.

[Tintop]

It's 10:15 why are you not at the track?    Good pics by the way.

I know what the comeback to that one is, but I just couldn't get away.

Sounds like you have released the information hounds, hopefully all your answers are forthcoming. I remember hearing about that 16 valve Piper CB750 but had left Van. before that.

It was suppose to rain, and was when I got up to check.  It was still raining when I started to post the pictures, now its not.   That said I went on Saturday while all that old alloy & bones were still running.

Yeah the Piper 750 was a neat bike.  Denis said when they received the head, oil passaged weren't drilled or didn't line up.  It was basically a machined prototype casting.   There are a couple of pictures on Denis' web site, in the history section under street.


Seems like a tough period to get info on.  CMA was in charge, but there were other series (Brimaco, later RACE) that had there own championships.  From all accounts the racing was great, but confusion rained otherwise.

[voxonda]

Wow, I love this setup! Beautiful frame.

Rob

[Tintop]

Wow, I love this setup! Beautiful frame.

Rob

Thanks Voxonda, as bwaller said, Denis does great work.  Can't wait till we start on mine.

[bwaller]

Seems like a tough period to get info on.  CMA was in charge, but there were other series (Brimaco, later RACE) that had there own championships.  From all accounts the racing was great, but confusion rained otherwise.


[/quote]

It was a confusing time with Brimaco in the east, CMA ran things in the west. Jimmy Allen (Dunlop Tires) had been #1 & was well admired in the east, Bob Work & Steve Baker out west. Crazy politics and power.

Reminds me a bit of the AMA and AHRMA et all.

I'll check with someone here who used to know everyone in the race game.

By the way completely goofy but here's a Brimaco sticker I stuck on an exterior door in 1975....pretty good material I'd say.

[Tintop]

Seems like a tough period to get info on.  CMA was in charge, but there were other series (Brimaco, later RACE) that had there own championships.  From all accounts the racing was great, but confusion rained otherwise.

It was a confusing time with Brimaco in the east, CMA ran things in the west. Jimmy Allen (Dunlop Tires) had been #1 & was well admired in the east, Bob Work & Steve Baker out west. Crazy politics and power.

Reminds me a bit of the AMA and AHRMA et all.

I'll check with someone here who used to know everyone in the race game.

By the way completely goofy but here's a Brimaco sticker I stuck on an exterior door in 1975....pretty good material I'd say.



[/quote]

Figures you have one of those.   Great sticker, and your right, it must be good material to have lasted this long through Quebec winters.

[bwaller]

Hey Brian,

Why not post something on the VRRA site requesting information? There are many "long of tooth" members who might shed some light. 

[Tintop]

Hey Brian,

Why not post something on the VRRA site requesting information? There are many "long of tooth" members who might shed some light. 

Already did - zero response so far.  Given what I have since found out will redo it though.