Kawasaki ZGRX 1200 Concours

[Wrider]

Excellent. I have been wrenching motorbikes for years but this is a level of expertise I could only dream about. Well done. Enjoyed the story!

[bergmen]

Originally Posted by Wrider

Excellent. I have been wrenching motorbikes for years but this is a level of expertise I could only dream about. Well done. Enjoyed the story!

Stay tuned, I have Phase III coming up...

Dan

[bergmen]

Okay, before I start on Phase III, I forgot a couple of details.

First, once I got the front fork situation worked out, there was one minor correction that needed to be made. I had a modern Z rated radial tire on the front (Avon something or other) but the rear still had a Metzler ME880 Marathon tire.

These two are about as compatible as oil and water. The ME 880 feels like it is made from recycled semi-truck tire casings with a little concrete and cast iron thrown in to soften it up a little. The handling was "okay" but I could sense and issue. So, I yanked the rear wheel and had an Avon Azaro (or something similar) mounted and balanced. That did it, now we were very much in synch.

Second, while I was at the National Rally, an interesting thing happened. A little history first.

Steve (in Sunny Florida) had developed a modification to the bevel gear on the Concours he called “the 7th gear” which was installing (after some customization) a gear set from the Kawasaki 1200 Voyager bevel gear case. I forget the gear ratios but it resulted in a 12% reduction in rpm across the board. Steve had recommended this modification for the ZGRX but I resisted thinking that it would dilute the power advantage by making the gearing too tall. It was a little spendy as well, around $450.00 IIRC.

So, at the closing banquet where all of the door prizes were being awarded we came to the last donated prize and that was a certificate from Steve for a 7th gear mod. I had won a trinket or two but that was it. The host called out the number and my buddy sitting next to me won it. He didn’t own a Concours but a Honda ST1300. So he immediately handed it to me (and I covered his hotel bill for the Rally).

When Steve heard about this he was astounded as to the coincidence. So that is why I had to go in and take off the bevel gear case AGAIN which I did during Phase III.

Stay tuned…

[bergmen]

Okay, on to Phase III which is replacing the 16” rear wheel for a 17” wheel to take advantage of modern radial tires. At the time there was a popular weld-up conversion by an outfit in Sebastopol (the name escapes me at the moment). This place was pretty famous for racing wheel welding and machining so a lot of Concours owners were sending their rear wheels in for conversion.

It was a bit expensive, around $500.00 I think and there was a long waiting list. I heard through the grape vine that a stock Kawasaki 17” wheel from a shaft drive cruiser might be able to be modified to work on a Concours. The wheel was from a Mean Streak model and I decided to gamble and buy a new one just to see if it could work.

I ordered one of the model year that had a black wheel (only one year had black, other years were various colors). When it arrived I did a fit-up and dimensional comparison. Amazingly, all features were identical to the Concours, axle size, bearings, rear drive coupling, everything. The only thing that differed was the rear rotor mount. The mounting surface was .300” inches closer to the right hand swingarm and it was a seven bolt pattern rather than a six bolt pattern of the Concours. The Mean Streak rotor was too large to work with the stock Concours caliper and mount so I went looking for a 260mm, seven bolt rotor. I wanted to stay with the stock Concours caliper and mount if possible. I found that a front rotor from another Kawasaki cruiser (can’t remember the model) was exactly what I needed. I ordered one.

I took the wheel down to the outfit that did the weld-ups and asked them to machine the rotor mounting surface down by .300”. He thought my idea was a lot smarter than his weld-up plan and jokingly said I would put him out of the Concours weld-up business. The machinist did this while I waited and he only charged me $100.00. When I got the wheel home I found I had to tap the rotor mounting holes a bit deeper because of the machining. No brainer, I had been doing this sort of thing throughout the project.

While I had the rear wheel etc. apart I removed the bevel gear case AGAIN and sent it off to Steve in Sunny Florida for the 7th gear mod. Bike was down for several weeks during Phase III in order to do all this at once.

In the meantime I had the mufflers powder coated with a high heat resistance wrinkle black finish, had several other parts satin black powder coated (front and rear foot pegs and brackets) and had an Avon 160/70 R17 Storm tire mounted on the new rim. The front had a 120/70 ZR 17 Storm tire mounted so I finally had a matched set.

[bergmen]

So now it was time to hit the road which I did in spades. Wonderful rides up into the Sierras totally enjoying the fabulous handling and power of the ZGRX 1200 Concours.

Here are pictures of some of my trips. Mike (horizontal) ended up this way by dissing the ZGRX (not actually, he has to lay down flat for his back but it makes a good story).

[Frame Maker]

Originally Posted by bergmen

... At the time there was a popular weld-up conversion by an outfit in Sebastopol (the name escapes me at the moment). This place was pretty famous for racing wheel welding and machining so a lot of Concours owners were sending their rear wheels in for conversion.

You're probably thinking of Kosman Specialties in Windsor. They were mostly known for their drag racing frames, but did a lot of wheel widening for local road racers.

By the way, really enjoy your write-up. Awesome project

[bergmen]

And there you have it. I rode this wonderful bike for seven years and enjoyed every minute of it. Fabulous handling, brakes and power. I ended up racing Jerry on his ST1300 and beat him up to 100+.

Though, all good things come to an end. I had gotten to the point that I was tiring of outdated technology and got excited when Yamaha announced the 2013 FJR 1300. It had everything I wanted in a modern motorcycle including throttle by wire, two ride modes (Touring and Sport) as well as an integrated electronic cruise control. The only thing I didn't like was the color, it was a slate grey and I was a red motorcycle guy at the time.

I thought if they came out with a red FJR I would be weak. The next year (2014), they introduced Candy Red FJRs and I was hooked, had to have one.

I bought a new 2014 FJR1300A on November 15, 2013 and have had it ever since. I eventually sold the ZGRX to a new owner in the Seattle area in August 2014 and he rode the pants off that bike for years and may still be riding it to this day.

Dan

[bergmen]

Originally Posted by Frame Maker

You're probably thinking of Kosman Specialties in Windsor. They were mostly known for their drag racing frames, but did a lot of wheel widening for local road racers.

By the way, really enjoy your write-up. Awesome project

Yes, that's it! Sandy was quite a character, really a kick to talk to. We immediately took to each other and spent more time talking motorcycles and racing than dealing with my projects.

I think he is out of business at this time but this was an amazing experience.

Thanks for refreshing my memory!

Dan

[budman]

That was awesome.

Love the pics out and about with your friends.

[Danodemotoman]

I am the current owner and rider of the ZGRX1200 that Dan did the conversion on.
I was looking for a narrative on the build and came across this forum. I have paperwork and many photos of the conversion.
It is still a impressive work of engineering including electrical modification.
The bike had about 73k mi on the frame and 30K mi on the engine when I acquired if IIRC.
Now has 109k mi.
I have had three C10 Concours prior. I found a bike that fit me!!! I have had newer bikes too including a 2016 Africa Twin. Currently have 8 bikes now two requiring modest work to return to service.
Cheers!

Trip to FL, color changed to Burnt Orange metallic and lower fairings re installed.
https://photos.smugmug.com/Motorcycl.../XL/003-XL.jpg

[Pushrod]

Gem thread.

[bergmen]

Hey Dan! Thanks for chiming in, great to hear from you! Glad to hear that the ZGRX is still providing smiles with the miles.

I am still riding my 2014 Yamaha FJR although a lot less these days as I get older. It is in hibernation right now due only to weather, about to be uncovered and ridden when my left shoulder returns to normal (surgery on 10/28/20) and should coincide with Spring.

Dan

[gixxerjeff]

Originally Posted by Pushrod

Gem thread.

^So much this^
And the drive-(ride)-by cameo from Dan representing a sighting of one in the wild just adds to the "Gem-ness) of this thread.
I will continue to "stay tuned".

[pepesm]

Damn, good read.

Used to have a ZRX1200 and it was a kick-ass bike.

"Eh,what, why is this Concours going by so fast?!?!?! That's not normal!" said the rider of a bone-stock Concours.

[islemann]

Fantastic thread. I put hotrodded one of my ZG's with valves, cams and carbs from a Ninja 1000 ex-drag bike into an old '85 Concours, it rapidly earned the name "ConcZilla". I didn't get a 25% gain like you in power - but it was enough to make the bike a fabulous back-roads sport-touring strafing machine. Thousands of miles of smiles.