GS1150 ES Makeover Project

If I recall from my car enthusiast days, when they lighten the crank and bevel the counterweights, its called knife edging, which along with lightening it, makes it more "aerodynamic" as it spins.

This is the bottom end of one of my go fast rockets. Besides the aerodynamic aspect, knife edging is also to shed any motor oil that might land on the throws that makes it past the windage tray/crank scraper keeping the crank in balance
and the oil where it needs to be.

[dorkburger]

If I recall from my car enthusiast days, when they lighten the crank and bevel the counterweights, its called knife edging, which along with lightening it, makes it more "aerodynamic" as it spins.

[Agemax]

i believe polishing a crank (and con rods) is used to remove imperfections, improving stress relief.

[londonboards]

I'm guessing it reduces drag from oil and air resistance.

But what the heck - it's beautiful.

Wow, I didn't know polished cranks where a thing.

I believe the idea behind them is that a polished crank is less likely to hold onto oil film as it spins thereby minimizing parasitic losses. Considering that was a Busa crank and the power levels those crazy b*stards go for I can't imagine it'd amount to more than 1-2 hp but I guess in some circles that's everything.

[eil]

Wow, I didn't know polished cranks where a thing.

[londonboards]

dorkburger - yes thanks. I will get there in the end.

I wanted to ask the guy if he would spend a day with me and tell me some stories. I wanted to pick up every engine piece and ask it's history and how it came to be in his shop (and obviously some of them abandoned in his shop too). Really interesting guy (just like some of the guys on this Forum who could tell some great drag racing stories) - he also was into hydroplanes with 2 stroke engines. This was him in the 1980s:

This is some Busa crank work he has done:

and if you ever wanted to know how a crank was balanced. Here is a GT750 crank being done:

Greetings

[dorkburger]

I love the old school "unsanitized" shop with parts, etc floating around....I could only imagine that there's some good stories there after 30 years. Richard, you are one busy fellow. I hope the 1150 project finally turns up some good luck. Sound like with the lengths you're going its an inevitably.

[Charlie G]

Thanks for the clarification. I'll be following along.

cg

[londonboards]

Here's a quick recap as to where I am with this project.

I bought this bike blind on eBay and it turned out that the motor was shot. At some stage it had had a clutch explosion and whilst all the broken parts had been replaced, there was still this little lot spinning around inside:



This had caused some major damage. At least one of the main bearings on the crank was shot and the camshafts and the saddles in which they sit in the head were shot. So the crank and the head were toast.

I found another motor in Holland and after doing a little investigation into it, I decided to install it and see what it was like. So far it is in the frame but I need to work on wiring it up and putting the carbs on to see how it fares.

In the meantime, I took the old engine apart completely, ditched the head and sent the crank shaft away to be fixed. I found a local guy (only 60 miles from me) who has been reconditioning cranks (and particularly GS1150 / GSX1100 cranks) for the last 30 years. This is his workshop:



This is the crankshaft balancing kit:



There are crankshafts all over the place:



So now I have the engine that is in the frame and another engine that I will rebuild. The rebuild one will be tip top, as it will have a brilliant crank (I think he will end up replacing all the bearings and rods and balancing it and welding it back up), I have 3 heads to choose from and 5 clutches. I will replace all the seals and the drive shaft bearings and even the other transmission bearings if there is the slightest doubt about them. I should end up with a great engine which I will then put into the frame and then work on the one that is in the frame.

So my winter projects will be to rebuild the old engine with the new crank, determine the condition of the new motor (by getting it fired up) and continue to restore my Dad's GS1100G (see my signature).

I think I should get the bed put in the garage first thing tomorrow.

Greetings

[Grimly]

Well, from what I saw of my mate doing it, it's considerably easier if you take all the bolts out before laying it down. He was quite accomplished at it, I must admit, and it's a technique I never got around to trying, but next time I'm doing one on my todd, I'll do it that way.
Even better, for a gearbox strip on a GS650G, was a top-down strip with the engine still in the frame - head, barrels, top engine case all come off and leave the gearbox internals exposed for replacement.
I have to take the '79 lump apart soon, so either of the above techniques will be in use.

[londonboards]

Grimly - I tried that once:

[Grimly]

I got quite good at swapping the 850 lumps in and out single-handed, but there was always a bit where a second pair of hands was invaluable. One of my friends simply laid his bike over and lifted the bike off the engine, leaving it on the floor - reversing that to install it.

[Rob S.]

Cool blog. Reminds me of the time I switched a 327 for a 350 into my '68 Camaro single handed. Or switched engines on a VW Beetle mostly single handed.

My kind of guy. Keep it going.

[londonboards]

"New" Engine Install

So I'm getting the new engine put in now.

See my GS1150 ES Blog - Engine Install (hi-res pics there).









Then I got a couple of helpers to raise the motor a little and pulled the platform out and rested the motor back on a car jack so I could line up the bolts.

Greetings