Author Topic: Steve Mclaughlin CR750 (Read 16807 times)

spiritof67 · « **on:** May 11, 2012, 08:51:04 AM »

There's always a lot of talk in SOHC4 about the Dick Mann/Bob Hansen Daytona bike, and it was historic. But there were a lot of other successful CR race bikes in the US and around the world in period - could we start a thread about them? I mean, there's Peter Darvill's World Endurance Championship bike (the last privateer winner of that title?), there was a Dutch endurance race won by a CR, and there's always the Morio Sumiya bike, so nicely recreated and shown in SOHC4.

My interest is in Steve McLaughlin's CR750, which was a "kit" bike but a damn serious one. Bob Braverman (God rest his soul..) did a whole series on CB750's in the old Cycle Guide magazine and he did a full pictorial on the McLaughlin Motors CR750. I'm not talking about the Daytona ride he had in 1973: I mean the bike he rode all over the US, California and Canada that was built in his shop in 1970. It was a mind-bending bike for its day. In a time when 99.9% of all race bikes were on wire wheels and had a drum brake in the rear, Steve's bike had Kimtab magnesium (not "mag") wheels and a disc brake in the rear. It had a magneto running off the end of the cam tower - that's right, not off the end of the crank. There were lots of other "demon tweaks" on the bike.But I have never even heard it mentioned in the Forums, nor have I seen any pictures of it. He developed the bike to the point where it had a Rob North/BSA style fairing and seat (better streamlining) and a lot of other stuff. But after Honda's strangely typical half-a##ed try at a Daytona win in 1973 (which they could have had, with basically the same bike that won in '70....) he changed over to a Yamaha.

For those young people out there or those who don't get out much, Steve McLaughlin was the inventor and first promoter of World Superbike racing. Yeah, that guy. Put US Superbike racers on the map. Gave Fred Merkel his chance and he won two World Superbike championships. As for Steve, he won the first official AMA Superbike race at Daytona in 1976 among other things. Good enough? Yeah I think so.

So, anybody out there gotten outside the easy-to-reach Mann icon? If not, let's try!

Anybody out there got any info, pictures, etc. on some of the OTHER successful CR racers, including Steve's bike?

voxonda · « **Reply #1 on:** May 11, 2012, 09:02:12 AM »

Let's go for it! Although a massive achievement and admire Dick Mann for his capabilities, never was much into his factory ride. Found the Yoshimura Cr750 Gary Fisher rode much more interesting, and the later Morio Sumiya bike much better looking.
Maybe McLaughlin's bike looked somewhat like this?

http://www.hondachopper.com/garage/articles/yoshi_750/page1.html

Cheers, Rob

Sam Green Racing · « **Reply #2 on:** May 11, 2012, 09:17:22 AM »

How about Big Grizzly

Read all of this thread, it gets better as it goes, you'll see what I mean.

http://forums.sohc4.net/index.php?topic=79001.0

Sam.

Darvill Racing · « **Reply #3 on:** May 12, 2012, 11:21:34 AM »

I'm all for it...

But then I am somewhat bias ;o)

Got loads of pics (and I know Rob has too!)

Regards,
Alex

spiritof67 · « **Reply #4 on:** May 12, 2012, 12:51:16 PM »

Glad I broke the ice on this. In answer to the question about the Dale-Starr-Yoshimura-Cooley bike: no, not really. Steve's bike used a mag running directly off the camshaft..it was a Honda CR "kit" bike so it had the Daytona 6.2 gas tank just like the Mann/Hansen bike, and the same fairing and seat....and the "kit" central oil tank...it had the modified valve cover with the through-bolts, first time I ever saw them and before I saw it available from RC Competition.

So people have pics? Get 'em on here. And anyone who has good pictures of the McLaughlin Motors CR750 please contact me. I have all the parts for a CR tribute bike and I think I'm doing a Steve bike.

Darvill Racing · « **Reply #5 on:** May 12, 2012, 01:24:16 PM »

I don't knowingly have any pictures of the McLaughlin bike and would be keen to see this, can anyone help?

I have many pictures of Peter Darvill's bikes (old and new), too many to post on here, please check out our gallery where you can navigate to our Flickr site, if there are any particular pics you would like to see on here I would be more than happy to post them.

spiritof67 · « **Reply #6 on:** May 12, 2012, 01:58:45 PM »

re: John Fuchs, I am pretty sure I saw him race in period either (both?) at Pocono or Bridgehampton. Didn't he also race a "stock" CB750 in the "Production" races back then? I seem to recall him doing that...'70 - '71?

And as for "Grizzly", isn't that Grizzly Competition, who were kind of the "other Yoshimura"? I have some parts I bought from a company by that name back in the '70s - same people?

OK, some leads on the "Steve Bike".
Steve set a new Open GP lap record with the then-McLaughlin Motors CR750 (1:38) racing at Willow Springs on Oct. 31, 1971,lapping all but 2nd place. This was the bike with the "BSA Daytona" style high seat but still 4 into 4 exhausts. The Steve bike had each pair of pipes braced together twice on each side.

Mclaughlin also raced the bike at Westwood, BC (actually Coquitlam BC) on July 29-30, 1972. He and Jim Chen (Yoshimura's "guy" back then) raced CR750's. By then Steve's bike was called the "Action Fours Honda". Steve finished 2d in the Unlimited race, with Chen 3rd. Reporting of the day said that both CR's seemed "down on power". That was with the 4 into 1 exhaust.

The "Grand Prize" in the Steve Bike thread is that Cycle Guide magazine (you young folks probably never heard of that one..) which in the March 1972 issue did a 5 page article on the machine, showing the engine internals, the Spalding ignition system (and I am sorry - it's not a magneto. It looks like a Spalding electronic ignition, surely the most advanced CR ignition of the day..) and noted that the McLaughlin machine used CB500 upper and lower triple clamps. By the way: they let Cycle Guide Editor Bob Braverman ride the bike as well.

And just to really get things going, in 1973 McLaughlin Motors built a street replica of the fully evolved bike, complete with Kimtabs/triple discs/BSA "Daytona" fairing, 6.3 gallon Daytona tank (Read Titan, but the Honda CR shape) et al for a guy named Doug Pushak. It was one of the stars of the "Cafe' Racers" issue of Motorcyclist magazine - November 1973 issue. Pushak (per McLaughlin common practice?) also let the Motorcyclist people ride his Honda. It was also the inspiration for me to start accumulating parts for a bike I'm just starting to build....

Spirit

voxonda · « **Reply #7 on:** May 12, 2012, 02:10:51 PM »

Maybe this one:

Retro Rocket · « **Reply #8 on:** May 12, 2012, 03:58:37 PM »

Subscribed...

spiritof67 · « **Reply #9 on:** May 12, 2012, 05:22:16 PM »

The paint job is different (this was the '70s, so panel paint was popular) but that looks like it...the original paint job was overall black with pearl fuschia and yellow stripes...but the fairing, wheels and rearsets are correct. The rearsets didn't have all that drilling then, and the muffler was a standard 70's "sausage". But it did have those red ties on the oil lines, and I checked the location of the bolts on the windshield and they are also correct. Where is that bike now?

Spirit

fang · « **Reply #10 on:** May 12, 2012, 06:25:00 PM »

Quote from: Retro Rocket on May 12, 2012, 03:58:37 PM

Subscribed...

me too!

spiritof67 · « **Reply #11 on:** May 12, 2012, 08:35:23 PM »

Looked again: that's the bike, unless some mad genius put the rear master cylinder reservoir in exactly the same place.
By the way, there was originally a helmet painted in the same colors as the bike.

By he way, in the same issue of Motorcyclist (November '73) there was another CB750 based cafe racer which also used Kimtabs with triple discs "Ken Davis of North Hollywood" who ran what looks to me like a Read Titan upper fairing with the standard tank and a race type saddle - and the fork tubes pushed up what looks like an inch. My recollection of that technique and the 19" front wheel led to rather interesting handling...and sometimes the front tire contacting the exhaust and/or upper frame tubes.

benjy · « **Reply #12 on:** May 13, 2012, 11:42:30 AM »

Spirit,in that cafe racer article,the honda with the kimtabs was black + bright panel painting.there was also a silver honda with a norton type petrol tank + 4 black pipes.
they said the 19" rear wheel was for more ground clearance,which was wierd even then.

MRieck · « **Reply #13 on:** May 13, 2012, 06:48:52 PM »

Quote from: spiritof67 on May 12, 2012, 05:22:16 PM

The paint job is different (this was the '70s, so panel paint was popular) but that looks like it...the original paint job was overall black with pearl fuschia and yellow stripes...but the fairing, wheels and rearsets are correct. The rearsets didn't have all that drilling then, and the muffler was a standard 70's "sausage". But it did have those red ties on the oil lines, and I checked the location of the bolts on the windshield and they are also correct. Where is that bike now?

Spirit

Parked in a garage located in "who the f knows ville" next to the MG in the background. Just a guess.

spiritof67 · « **Reply #14 on:** May 13, 2012, 07:30:03 PM »

re: that oddball 4 pipe "cafe racer" in the Motorcyclist article: the text says the bike was regeared so high that you had to downshift to reach 115 mph. Now that's what I call accepting style over function, dude.

This while a whole army of other guys were trying to figure out how to make an 18" front wheel work on a CB750. By the way: never did work. On another thread though, the 19" wheel combined with CB500 triple clamps....it's one of those old school things that kinda got lost in the new era. has anyone tried it - or instead tried changing the geometry to simulate the change? Ican recall a whoke community of CB750 people trying to do this with different rolling radius tire sizes. Has any contemporary experimenter (Moonpie?) tried this, and if not, why not?

We've changed virtually every other part of the hoary CB750 to make it better. Has anyone (recently) tried this, or is this another place where we need to restart the research? Steve did it and it worked - and that was 1972. Why not now?

Retro Rocket · « **Reply #15 on:** May 14, 2012, 05:15:48 AM »

Terry {Terry in Australia} had a beautiful K2 with an 18 inch front wheel and it handled extremely well, actually he said it was the best handling 750 he ever rode.... {fzr1000 41mm forks and custom made clamps}

MRieck · « **Reply #16 on:** May 14, 2012, 05:54:02 AM »

I have run an 18" rim for over 20 years.

voxonda · « **Reply #17 on:** May 14, 2012, 05:58:07 AM »

I started with the 750 early '70s like the lot and very early on changed to 18" and never looked back. Use triple of own creation or, lately, the triples from the DOHC series 900. And use longer swing on one of the racers. Also changed to 20 m/m front axle and found that was one of the single best upgrades.

spiritof67 · « **Reply #18 on:** May 14, 2012, 07:14:36 AM »

Sorry, all - what I meant to say was "...18" wheel never worked with standard forks and triple clamps or without other mods". That's (backwards) what I meant when I was talking about tire rolling radiuses being looked at as a way to get changes similar to what you could get if you changed triple clamps. I mean,I recall an article in CYCLE about cafe racers and there was a CB750 with an 18" on the front - and a nice big steering damper, which the owner/builder said it really needed.

OR, as I sugggested, you could just "do what Steve did': change to CB500 triple clamps. So again I posit: is this ancient technology that was successful but either little known or forgtten? Steve's bike was arguably the 2nd most successful CR bike in America or a least the highest profile one, and certainly was competed over a long period (nearly 4 years). If this is what he did, and it apparently worked, .....?

Oh, and as usual: where's that bike now?

Spirit

Spirit

754 · « **Reply #19 on:** May 14, 2012, 07:28:32 AM »

Worked for him..maybe not for everyone..
Worked for Honda too when they did it on all the 750s

turboguzzi · « **Reply #20 on:** May 14, 2012, 08:41:34 AM »

dean adams of superbikeplanet.com will have some pics....

recall seeing a quite a few rare cr pictures on his site

spiritof67 · « **Reply #21 on:** May 15, 2012, 10:16:02 PM »

Maybe I needed a space suit and Lunar Rover but I couldn't find anything on that site about CR750's. Then again, I'm not enough of an anorak/trainspotter to look at evey reference in his site for it, either.

Now: anybody got any pictures of Steve Mclaughlin's CR750 to share? Either the Honda CR fairing or the BSA triple fairing versions?

Spirit

spiritof67 · « **Reply #22 on:** May 16, 2012, 05:12:43 PM »

OK, since no one will step into the breach, here goes.Courtesy of the great Bob Braverman, one of America's greatest motorcycle journalists and CYCLE GUIDE magazine, long since out of print: The Steve McLaughlin Honda CR750. For some reason I have never seen a picture of this machine on any of the vaunted CR websites, though I believe it to be the single most successfully competed CR750 of them all. anyway, see atached. First of a series.

spiritof67 · « **Reply #23 on:** May 16, 2012, 05:14:51 PM »

Second of the series....

spiritof67 · « **Reply #24 on:** May 16, 2012, 05:17:10 PM »

Third in the series...and check out the Spalding Flamethrower CD ignition adapted to the cam tower..

News:

Author Topic: Steve Mclaughlin CR750 (Read 16807 times)