View Full Version : ROLLER CRANKSHAFT
I plan on racing a Suzuki 1100 Motorcycle this year. It has a multi unit pressed together crankshaft. How would I true it and then pin the journals and rassemble?Once pinned I would like to weld(TIG IT) it after final trueing. Anyone have any ideas or actual previous experience doing cranks? This is a four cylinder model.Thanx
04-09-2002, 03:36 PM
Tell me, this has got to be a wind up.
Does April 1st come later in Canada?
For a start you can't pin them the pins are hardened and if you tig it how do you fit new bearings later?
04-09-2002, 04:53 PM
If he clamps a temperature compensating flux capacitor to the underside of the crankshaft (opposite where he is welding), he can draw the heat away from the area that the journal bearings are mounted. I saw that done on "X-Files" once, I think?
Might have to put a black hole diode close to it to help suck the heat, but hey!......might be worth a shot. How bout it??????
04-09-2002, 07:16 PM
If it were my machine, I would look for an aftermarket one piece forged crank.
Reason; a multi-piece crank will never have the strength and stability that a forged crank would.
Honestly, by drilling and doweling the crank you are actually creating areas of structural compromise. And then the welded areas would also be a concern because of the possibility of causing stress cracks from the heat.
But don't forget the additional cost of all new bearings for the crank, plus the time plastigauging and fitting the bearings.
It will be worth it if you are serious on racing. Also consider an external oil cooler. And if you do that, don't settle for anything less than a 5 fin cooler.
Hope this helps...
04-09-2002, 08:26 PM
Flux capacitors are prohibitively expensive as they are made by Delorian. Black hole diodes are getting really hard to find since being replaced by the bidirectional monode.
04-10-2002, 01:22 AM
I don't think somethink like a one piece forged crank exists for these machines.
All the production racers have the pressed cranks and have had them for years with no problems. Engine reliability isn't such a problem as it was years ago due to technology and the amount of development that's put in by the manufacturers.
Ironically enough I was at Cadwell Park race circuit yesterday with my Son in Law who was testing his production Yamaha 600. There were 24, 8 lap sessions during the day for the various groups. To my knowledge there were no retirements through mechanical failure, a fact that was not possible some years ago.
There were no Suzuki 1100's present but there were some 1000's. These in normal off the shelf production trim were hitting 165 down the back straight. Cadwell Park incidently isn't a speed bowl type circuit but a road type circuit going up and down hills and through woods etc.
Incidently Black hole diodes are for two strokes not four strokes.
If you have got to weld it you could try keeping it cool by blowing non ferrous de-ionized gas through a length of fallopian tube at the weld area.
04-10-2002, 01:54 AM
For God's sake man, if you want a Harley, sell the rice burner and then you can have a roller bearing crank. Oh, sure - they leak all over tha place, but if carefully placed on a scotch-garded white carpet leaks and tears downs only offer minimal cleanups (but not for you, that is why you have the 'ol lady - that's HER job, right!).
And it is a known fact that true audiophiles require the oxygen free linear crystal black hole triodes for that full bodied sound stage as the "old technology" diodes are so yesterday...
04-10-2002, 07:14 PM
First I will assume you are going to drag race the bike. It is the shock of letting the clutch out that moves the crank flywheels out of true.
First you need to measure the areas between the crank flywheels where the rods are. Record these demensions for later reference.
You will use these numbers when reassmbling.
Then press the crank apart, making surre to number each flywheel for reference. Install
new bearings that are uprated to carry more load. I f the bike is a modified or pro-stock
class bike then also lighten the flywheels.
Then reassemble the crank. Now the hard part
you need to true each flywheel, you will need to hold a tolerance of .0005" TIR. The
higher you will rev the bike the more important this is.
The above is a lot of work but once all of that is done then you will weld the crank pins. When welding you have to be carefull
not to warp it out of true. Oh you are just welding the crank pins!
Now you see why Bob at Falicon charges so
much money to do this.
Oh I forgot, yes the crank is still rebuildable after this is done.