8 valve head ?

[gggGary]

Daddy G; suzuki welded 1100 4 valve cranks, they even had a recall and tore down and retro welded a bunch of early 4 valve cranks. I had a stocker, you could see the welds without a tear down if you knew where to look, it was must do on those engines. There is a great article about "pops" Yoshimura that touched on this.

 

[CDNTX650]

Floris quit being an idiot. I understand it CAN be done.....I am mechanic enough to know it will require hugely deep pockets if you are not jerry heiden or some kind of fabricator and i understand his skills. Merely getting to the point of for custom one off work like that $$$$$$$$$$$$$$$$...get the picture?. Probably not since you asked.

 

[CDNTX650]

And yes...big inline 4 cranks should be. Apparantly over revs like a missed shift can twist them pretty easy

 

[member3480]

Gary I owned GS1100 from 1981 to 1983 and also owned two 1150 and never had a crank from any of those bikes come with a welded crank from the factory. Are you talking about the ends being welded or the pins. I never had one which is weird and all my cranks went to Falacon in Fl and were welded and balanced. When you welded the pins you could see the welds if you took off the jugs. You only had to half moon the welds. I have a 1982 sitting here and its not welded. Could this have been a one year run???? and what year .... I raced a 1982 and it was welded by Falacon Now you got me thinking and going to have to look it up. I know the 1100 KATANA was a little different but not much. Here is a picture of one done and a clutch basket done. Crank was not done from factory.

 

[gggGary]

I'm no expert but I had a used 82? GS1100E that had been a plain Jane street bike bags and full windshield. I found gurus that told me this, the one I had was welded....
"QUESTION: Is crankshaft welded? - 1982 GS1100E

My bike was manufactured Feb. 1982. How can I tell if it has a welded crank?

RIDER: David S. Corwin

REPLY: Scott Horner
Remove the clutch cover and the clutch hub. You will be able to see the throw just prior to the # 3 rod on the crankshaft. Rotate the motor until you can see where the male end of the prior throw is pressed in (it will be round, roughly 1 1/4"). If there is a semicircle of weld, you are set. Good Luck!"

Here's the read on Yoshimura and Suzuki development.
http://slcelectronics.com/GS1000_Build/Yoshimura-specs.pdf
There's a very interesting tidbit in there about crankshaft assembly!

 

[member3480]

Gary I beleave you and I just pulled up 5 cranks off ebay and internet all were not welded. I am going to read the article. I know there was a problem with the stator end and they did fix that by adding a weld. I owned no lie 15 of these bikes and not one was welded. If you pull the clutch you are looking at the gear and yes you can see one pin. So if you seen a half moon weld on the pin it was welded. I use to change the gear to 750 straight cut gear and upgraded basket for better performance. Thanks for the info now I got to read this and try to figure out why I never got one. Bike in picture above is 1982 and crank was not welded until I took it out and had it done.

 

[weaselbeak]

If you do a search, you will see that Suzuki started welding cranks on the 1100 in mid 82. When I had my clutch beefed up the shop owner bragged that Suzukis were welded and Kaws were not. It was easier and cheaper to pump up the big Suzukis. My 82 was welded. I do believe the discrepancies in stories comes from the cranks not being FULLY welded. The higher load end was welded, because that was where the problems occurred. The other end was apparently not.

 

[gggGary]

Jury is out on the welding, this thread from the GS forum and other members there, is where I got the welded thing from. But even in that group there were some differing opinions.

"eddy21 wrote:
The Crank twisting went on till 83 when they started using a locktite type solution. Don't forget the left side crank ends breaking off on built motors . Guess should have copied Z-1 a little closer.

They started welding the crank throws half way through the '82 year model. If you have an '82 and are not sure if your crank is welded, you can take the clutch cover off, pull the clutch assembly and rotate the crank until you see a weld on the crank. If you rotate the crank 360 degrees and do not see a weld then you have a motor without the upgrade. Locktite was not the solution.
Hap

And this;

"I don't think the 80-82 non welded cranks are a toss up for street use, it is more like a low probability of twisting a factory crank/street riding. While the 83 welded crank is preferable, I don't think anyone would steer you away from an 80-82 1100E that you might have found that meets your fancy."

 

[cowboy3669]

I had to weld the crank on the dragbike. With the turbo and nitrous the crank would move.In the 1/4 will hit 10k rpm.

 

[member3480]

Yes I do agree that the ends were welded from the factory because the weight of the stator use to break the end off. Had early 81 bike do that to me. But I still am out on the complete crank being welded from the factory. I called a buddy of mine who owns a KAW/SUZ dealership and use to drag race with me years ago and he too cannot recall a complete crank being welded from factory. I owned 15 of these suckers and I would have loved if the factory welded the crank it would have saved me thousands of dollar sending them to FALICON HAHA . When I go back to my garage I am going to break my bottom end down and look for the factory weld.
Its great that sites like this have many old timers like me that can remember the older bikes.
Cowboy How much boost are you pulling and how many trans did you go threw. Are you running gas or Alky. I have built over 25 turbo KZ and GS and only did one twin and was not impressed with the power. I know you are just a 1/4 mile bike but what HP do you think you are getting out of motor. I think I read somewhere you run mid 10;s

 

[cowboy3669]

I running 13# of boost. Running gas,nitrous setup. Runs mid 10's. I have not really had many trans. problems,had a couple that would stay in 1st. The dogs were wore out.Not sure of HP but the bike and I weight 705 lbs. and run 125 mph,with best of 133 mph.

 

[member3480]

WOW that's good for the weight. You fat or bike HAHA Every 7 pounds of weight lost more ET. I have three bikes that run at the track that I keep going and same problem with one of my Hayabusas My rider is 220 lbs and bike won't go any faster on motor than 9:70 but I put one of the other lighter riders on bike and he is 140 lbs and bike ran the numbers 9:40 that it should run on motor. I also have one that runs high 7's with 200 lb rider with the bottle. I started drag racing Triumphs in the late 60's and then go crazy and built all kind of JAP bikes and then lost my mind and built and rode Top Fuel Harleys. NO BRAINS in the attic. Then got sick and had to give the riding up now I just build motors and go to the track to make sure they run. Its a great sport but costs big money. If you have a video of bike running I would love to see it. If you have one send it to DADDYGCYCLES@YAHOO.COM
CONGRATS on your Drag Bike
Rich

 

[cowboy3669]

I weight 230 before leathers and helmet.There is a video of the bike will try and get it to you.

 

[floris]

Hello there,
My XS is finally build up.
It's been completed this summer.
I have a big bore kit up to 900 cc and lots of goodies.
All in all i'm satisfied with the result.
70 Hp on the bench and lots of torque.
Not a normal bike in comparisen with mine comes near.
Not even my budy who'm drives a Beemer R75 up bored up to 1000 cc.

I crush them all.

So i'm content with the results so far.

Jerry however is still working on his XS 500 cc factory like racer.
Meaning he's downsizing to 500 cc with a 8 valve head.

We'll see how this project turns out.

Maybe it's something to consider for my next project.

A yamaha based 4 stroke racer, like it could have been build by the factory in the sixty's.
I'm thinking about the 3 cilinder XS 750 with dardan and build it to chain driven.
The why ?
Because it's pausible.
What more is there ?

 

[floris]

Also,
in case you might wonder what's became of my XS 900 project ?

Take a looksee at my Facebook.
Floris Fledderus.
And see in the pictures.

 

[kopcicle]

I wasn't going to waste the bag of popcorn on this one so I stayed clear early . Now that inevitable thread drift has subsided I'll chime in .

I'm surprised no one mentioned Kevin

Now on to the why , as if it matters .

Before 6,000 RPM the 2 valve wins
After 8,000 RPM the 4 valve wins
These are estimates so Your Mileage May Vary (YMMV) . However the real point is there is no way the 4 valve can keep up with the 2 valve on the bottom and likewise the 2 valve can't compete with the 4 valve on top . That is already in the thread and correct .

Once again people , the first limiting weakness in the XS is the center crank pin . In 360 ,180, 270/90 , 277/83 , 284/76 I've seen carnage from all these combinations . It does seem to happen later in the rev range with the 277/83 and the 284/76 but it happens . The 180 degree crank failures were spectacular . More another time on the how or why but the weak point was and is the center crank pin . Welding the center pin and the crank throws only delay the inevitable .

The crank is reasonably well supported for nominal use below 8,000 RPM but the case itself begins to move if the RPM's are regularly pushed above 9,000 . It isn't so much the RPM's that kill the assembly as shock loading the crank at any RPM . It just happens more suddenly and explosively at elevated RPM's

Improving the quality of the case fasteners just transmits the forces back to the crankshaft . So we're back to the crankshaft center pin again .

Mrriggs has reinvented the XS yet again

Brett has found out what the tuners and builders of the past used to experiment with oddly twisted crankshafts . Once you are not limited by the splines anything is possible .

Even if the crankshaft is strengthened , lightened , and supported , just short of 10,000 RPM it all goes wrong . This is where the 4 valve head is already far outperforming the 2 valve head .

So for those of you not interested in why or uncaring of my personal experiences .

Before 6,000 RPM the 2 valve wins
After 8,000 RPM the 4 valve wins
The crankshaft must be welded , pin and throw.
The XS650 can't reliably turn 10,000 RPM
The cases are the next weakest point beyond the crankshaft
Strengthening the cases places the stresses back on the crank
Once the cases are strengthened crank failures are spectacular .
rephased 270,277,284, crankshafts only delay the inevitable .

Just thought I'd share

~kop