engine pics

BohicaBob wrote:

Pops Yoshimura sold 987 cc and 998 cc piston kits for the '73-'75 Z1-900 and the 1976 KZ900/LTD 903cc motors of that era.

The '77-'80 KZ1000s had 1015 cc motors. Pops sold a dandy 1015 cc two-ring, slipper-piston racing kit back then that a number of roadracers of the day used, including Pierre Des Roche's Superbike Championship-winning 1978 Vetter KZ1000.

Funny you should mention that particular bike. I was in the airport in Newark N.J. back in June and facing an 18 hour flight to Singapore, en route to Australia. I made a quick dash to the mag store for some good reading material....found a magazine with an article on a collection of old superbikes...that was one of the bikes. I still have it here somewhere...I should scan the article an post it.

Larry C

BohicaBob thanks for the links to pictures of your bikes and the tire brake mod I enjoyed looking at them.

Pumps: You are very welcome.

Larrycavan and Modprod: On that Vetter '78 KZ1000, Pierre achieved 141 hp via: a 200% increase in head flow (with the help of CR Axtel, Manley 37.5 mm intake and 30 mm exhaust valves, and Yosh Bonneville cams), a Yosh 1015 cc two-ring slipper piston kit, a set of modified (read, re-engineered) stock Mikuni 26 mm carbs which flowed 185% of the stock 26s, etc. Pierre also modified the frame quite a bit to make the bike work on the track for Reg Pridmore.

Pierre inspired me to improve my Z1s' and KZs' engine and chassis, as did Pops and Fujio Yoshimura, Kaz Yoshima, Harry Maillet, and the other Z1 tuners back then.

In fact, I lived in LA at the time. Just for fun my biking pals and I would at times visit these tuners. I remember one time Fujio took me into Pops' dyno room where we looked over the results of some 998 cc Z1 motors they had built for customers: 124+ hp! Pops and Fujio were very approachable and friendly. Yes, I did purchase lots of Z1 Yosh parts.

Post edited by: BohicaBob, at: 2006/11/19 10:23

Post edited by: BohicaBob, at: 2006/11/19 11:09

larrycavan wrote:

modprod wrote:

larrycavan wrote:

modprod wrote:

Head bead blasted & cylinders sand blasted.

Where in the world did you get your hands on those old CRs? That's so cool!

Thanks for noticing Larry. Only the "real old school" guys remember them! I bought them new in the winter of 1980.The "Ticklers" are still good too. The bike I bought new in 1974. At one point (about 85 or 86?) I tried the Mic 33 smoothbores. They wouldn't touch the 31s with my old combination so the 31s still live on the bike today. The whole bike is a vintage "modified" (except the rear tire) of that period and still runs like it did 20+ years ago. I let a local guy ride it 2 years ago and it went a 9.43 and a 5.89 with a half dozen tries. He had trouble leaving with a standard clutch and no twostep. Go figure?

Impressive ET out of that smallish engine size. Great job!!! The entire bike gets a big thumbs up. You've done one heck of a job keeping the bike that nice over the years.

I'm a big fan of Keihin CR carbs. It's so rare to see them on a KZ these days. They caught my eye first thing in that pic.

Thanks Larry, the head on this bike (36/31) was done in 1978 by Mark MacIntosh of M&M Racing and later (1980) the Crs were added along with Norris cams (460-448). As you said it is the "combination" that made it work not just the parts and pieces. Brad Matte put new valves (titanium) in it in 2000 and saved it. Brad told me at the time, "no sense changing a working combination" and he set them up as it was in the mid-80s. I know that a later model port design/cam/carb combination could yield better results but why bother? No records to chase anymore. I always enjoyed it when guys came around here with bigger motors but didn't have the proper combination and could be beat by a little "old" motor. I still talk to Mark M. weekly and we love to talk about the "glory days". I think I'll keep it.

BohicaBob wrote:

Pumps: You are very welcome.

Larrycavan and Modprod: On that Vetter '78 KZ1000, Pierre achieved 141 hp via: a 200% increase in head flow (with the help of CR Axtel, Manley 37.5 mm intake and 30 mm exhaust valves, and Yosh Bonneville cams), a Yosh 1015 cc two-ring slipper piston kit, a set of modified (read, re-engineered) stock Mikuni 26 mm carbs which flowed 185% of the stock 26s, etc. Pierre also modified the frame quite a bit to make the bike work on the track for Reg Pridmore.

Pierre inspired me to improve my Z1s' and KZs' engine and chassis, as did Pops and Fujio Yoshimura, Kaz Yoshima, Harry Maillet, and the other Z1 tuners back then.

In fact, I lived in LA at the time. Just for fun my biking pals and I would at times visit these tuners. I remember one time Fujio took me into Pops' dyno room where we looked over the results of some 998 cc Z1 motors they had built for customers: 124+ hp! Pops and Fujio were very approachable and friendly. Yes, I did purchase lots of Z1 Yosh parts.

Post edited by: BohicaBob, at: 2006/11/19 10:23<br><br>Post edited by: BohicaBob, at: 2006/11/19 11:09

I think that's really great Bob! What a great experience! You got to hear it from the "masters" of the day at their peak with the best equipment of the time. You can't beat that. Technology is always relevant only to what is available at the time and these guys were the best.

BohicaBob wrote:

Pumps: You are very welcome.

Larrycavan and Modprod: On that Vetter '78 KZ1000, Pierre achieved 141 hp via: a 200% increase in head flow (with the help of CR Axtel, Manley 37.5 mm intake and 30 mm exhaust valves, and Yosh Bonneville cams), a Yosh 1015 cc two-ring slipper piston kit, a set of modified (read, re-engineered) stock Mikuni 26 mm carbs which flowed 185% of the stock 26s, etc. Pierre also modified the frame quite a bit to make the bike work on the track for Reg Pridmore.

Pierre inspired me to improve my Z1s' and KZs' engine and chassis, as did Pops and Fujio Yoshimura, Kaz Yoshima, Harry Maillet, and the other Z1 tuners back then.

In fact, I lived in LA at the time. Just for fun my biking pals and I would at times visit these tuners. I remember one time Fujio took me into Pops' dyno room where we looked over the results of some 998 cc Z1 motors they had built for customers: 124+ hp! Pops and Fujio were very approachable and friendly. Yes, I did purchase lots of Z1 Yosh parts.

Post edited by: BohicaBob, at: 2006/11/19 10:23<br><br>Post edited by: BohicaBob, at: 2006/11/19 11:09

Hey Bob I've lived in the LA area all my life and have a small Yoshimura connection too. I can a test to Yoshimura power also. I got to know Mike Valasco when he worked at Whittier Kawasaki before he worked for Yoshimura. Mike knowing I had a 77 KZ650 he asked if Yoshimura could use my bike as a jig for making headers, of course I said yes. Later I put Yoshimura pistons [716cc], road & track cams' 29mm smoothbores and my head ported & polished. My little 650 put out 85hp to the tire and high 11's in the quarter. I met Fujio and Wes Cooley At the little Yoshimura shop in Costa Mesa.
Mark

Mark: At one of Southern California's many swap meets, I bought some '75 Z1-900 parts (forks, tappets, etc.) from Mike Valesco that Yoshimura did not need or want for one of Yosh's Z1 Superbike racers around 1977 or so.

If I recall, Mike worked for Pops for a number of years before he moved on to doing his own thing, tuning and making exhausts, etc. I visited Pops' Costa Mesa shop a few times, but I mostly hung out at Pops' North Hollywood shop, which was incidentally a stone's throw from Kaz Yoshima's shop.

I vote for more photo's of the bike.


modprod wrote:

larrycavan wrote:

modprod wrote:

larrycavan wrote:

modprod wrote:

Head bead blasted & cylinders sand blasted.

Where in the world did you get your hands on those old CRs? That's so cool!

Thanks for noticing Larry. Only the "real old school" guys remember them! I bought them new in the winter of 1980.The "Ticklers" are still good too. The bike I bought new in 1974. At one point (about 85 or 86?) I tried the Mic 33 smoothbores. They wouldn't touch the 31s with my old combination so the 31s still live on the bike today. The whole bike is a vintage "modified" (except the rear tire) of that period and still runs like it did 20+ years ago. I let a local guy ride it 2 years ago and it went a 9.43 and a 5.89 with a half dozen tries. He had trouble leaving with a standard clutch and no twostep. Go figure?

Impressive ET out of that smallish engine size. Great job!!! The entire bike gets a big thumbs up. You've done one heck of a job keeping the bike that nice over the years.

I'm a big fan of Keihin CR carbs. It's so rare to see them on a KZ these days. They caught my eye first thing in that pic.

Thanks Larry, the head on this bike (36/31) was done in 1978 by Mark MacIntosh of M&M Racing and later (1980) the Crs were added along with Norris cams (460-448). As you said it is the "combination" that made it work not just the parts and pieces. Brad Matte put new valves (titanium) in it in 2000 and saved it. Brad told me at the time, "no sense changing a working combination" and he set them up as it was in the mid-80s. I know that a later model port design/cam/carb combination could yield better results but why bother? No records to chase anymore. I always enjoyed it when guys came around here with bigger motors but didn't have the proper combination and could be beat by a little "old" motor. I still talk to Mark M. weekly and we love to talk about the "glory days". I think I'll keep it.

I read that article too....I'd love to know how they pulled a 200% increase in airflow out of the KZ head with only a 37.5 intake valve...that's approaching Vortex territory....I've flowed some big dollar heads that just ticked over the 120% number and wasn't real impressed with them...

Wow...those names bring back memories of sitting in my apartment out in the country, all by myself with Cycle magazine...I used to love that mag because back in the day, they did complete analysis of engine builds. I haven't seen a magazine in many years that approached the technical aspects the way it was done back then...

What ever happened to Harry Maillet?...He build some of the trickest MKII's you could ever hope for when I was a young kid. Wasn't his shop called Performance Works?





modprod wrote:

BohicaBob wrote:

Pumps: You are very welcome.

Larrycavan and Modprod: On that Vetter '78 KZ1000, Pierre achieved 141 hp via: a 200% increase in head flow (with the help of CR Axtel, Manley 37.5 mm intake and 30 mm exhaust valves, and Yosh Bonneville cams), a Yosh 1015 cc two-ring slipper piston kit, a set of modified (read, re-engineered) stock Mikuni 26 mm carbs which flowed 185% of the stock 26s, etc. Pierre also modified the frame quite a bit to make the bike work on the track for Reg Pridmore.

Pierre inspired me to improve my Z1s' and KZs' engine and chassis, as did Pops and Fujio Yoshimura, Kaz Yoshima, Harry Maillet, and the other Z1 tuners back then.

In fact, I lived in LA at the time. Just for fun my biking pals and I would at times visit these tuners. I remember one time Fujio took me into Pops' dyno room where we looked over the results of some 998 cc Z1 motors they had built for customers: 124+ hp! Pops and Fujio were very approachable and friendly. Yes, I did purchase lots of Z1 Yosh parts.

Post edited by: BohicaBob, at: 2006/11/19 10:23<br><br>Post edited by: BohicaBob, at: 2006/11/19 11:09

I think that's really great Bob! What a great experience! You got to hear it from the "masters" of the day at their peak with the best equipment of the time. You can't beat that. Technology is always relevant only to what is available at the time and these guys were the best.

how about just a picture of a really big mock up motor,still needs lots of sanding and polishing!

larrycavan wrote:

I vote for more photo's of the bike.

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How about: Ohio Valley 1986 Dragbike H/M 1/8th National Record 5.97 115.68 (in the heat)


Post edited by: modprod, at: 2006/11/19 23:49

larrycavan wrote:

I vote for more photo's of the bike.

quote]quote][/quote]
Or something upto date: