6-speed trans in 1st generation / slabside GSX-R 1100?

[Gehr]

I've been lurking here for a few months

Edited March 30, 2022 by Gehr
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[dupersunc]

https://oldskoolsuzuki.info/archives/404

 

[Gehr]

Thanks, butt

Edited March 30, 2022 by Gehr
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[Gixer1460]

How about using the steel basket from the 1127 engines - maybe more clearance? Still amazed that peeps 'need' to try this in any 1100 ! ! !

[dupersunc]

1 hour ago, Gehr said:

Thanks, but the 1st generation GSX-R1100 is a 1052cc which is not listed anywhere in that post.

Yup, I already scanned through this website's archives & there is nothing listed I could find.

Same deal, 1052 or 1127. Ok I know the primary is differnt from 1052. 1127, but you are already swaping baskets on primaries.

[Joseph]

1 hour ago, Gixer1460 said:

How about using the steel basket from the 1127 engines - maybe more clearance? Still amazed that peeps 'need' to try this in any 1100 ! ! !

But it's awesome 

[dupersunc]

1 hour ago, Gixer1460 said:

How about using the steel basket from the 1127 engines - maybe more clearance? Still amazed that peeps 'need' to try this in any 1100 ! ! !

The 1100 ratios are shit for track work. They are touring ratios.

[wraith]

Why don't people just changed the sprocket size for the track they are running on like the old GP racers did, didn't see them changing complete gear box for one track with short straights and lots of bends they just changed the sprocket gearing.

cheeper, quicker and easier?

[dupersunc]

Just now, wraith said:

Why don't people just changed the sprocket size for the track they are running on like the old GP racers did, didn't see them changing complete gear box for one track with short straights and lots of bends they just changed the sprocket gearing.

cheeper, quicker and easier?

They had a better spread of ratio's to start with.    The 1100 ratio's are too evenly spaced, big drops between 3rd-4th-5th.   A race gear box has bigh gaps between lower gears, and small gaps between the top gears.  in the lower gears you are traction/wheelie limited so don't need to keep the bike in the fat part of the power curve, but in the top gears where you need to over come aero drag, you want the gears closer together to when you change up a gear you drop down the revs into a fat part of the power.

Modern 1000cc bikes do 100mph in first 135mph second, but might only be 15mph apart between 5th and 6th.

 

[Dezza]

Put an efe engine in it and just ride round in top gear all the time

[clivegto]

Turbo it and ride it on boost all the time 

[wraith]

Get rid of the traction control and anti wheel gissmos and ride the bike like a man 

[no class]

I knew 3 guys that did this 6 speed swap way back when it was cool…..and all of them had 2nd gear failures ….. fucking waste of time for the agrovation.

[Lachie04]

1 hour ago, no class said:

I knew 3 guys that did this 6 speed swap way back when it was cool…..and all of them had 2nd gear failures ….. fucking waste of time for the agrovation.

Yep

 

Edited February 18, 2022 by Lachie04

[Nik]

I made my first 6-speed 7/11 in 1991. At the time, little was known about exchangeability between years etc. I simply took my 1985 750 6-speed gearbox and put it in my 1127. The splines for the clutch basket were different, so I had the shaft's splines reworked (CNC spark erosion machine) to fit the 1127 clutch. Easy! Ive ridden it 140,000 km since then, hard, without any problems.

Later, I did other 6-speed 1127s by using post-87 750 6-speed gearboxes (same splines as 1100). Since the later main shafts aren't drilled (for the clutch push rod, from the left-side slave cylinder), I used the J/K 750 wire solution. No machining needed, and you get a better feeling from a wire clutch. 

I have built four 7/11 with 6-speeds (two more on the way), and I've never had any problems. I keep hearing "my friend did this", "I heard that ... " or "why do it, you don't need it on an 1100". The fact is that it makes a big difference. For me, and most who has actually tried it.

Concerning strength and reliability of a 6-speed; yes, the gears are slightly narrower, but I have never seen a street gearbox break because of that. It's the dogs that wear and break (and there are more dogs on the 6-speed gears, even if they're smaller). I've replaced more 2nd gears on my 5-speed 1100s than on my 6-speeds. 

Of course, you don't put a 6-speed in a proper race engine, but I would't hesitate to do it on a 140 hp engine.

My two cents ...

Edited February 18, 2022 by Nik

[Joseph]

I've been road abusing a 6 speed gearbox thanks to a 1216 with ported head, SERT cams, race carbs, race exhaust etc it's just had it's 5000 km service with no teeth in the oil pan yet. 

I always use the clutch and am not always thrashing it but i'm guessing it's a healthy engine pushing well over 150 ?

Like @Nik(although less mileage ridden) i would not want a 5 speed anymore nor a stock 1127 either come to think about it

 

Edited February 18, 2022 by Joseph

[Gehr]

Thanks, ha!

 

Edited March 30, 2022 by Gehr
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[manden]

On 2/18/2022 at 11:19 PM, Joseph said:

I've been road abusing a 6 speed gearbox thanks to a 1216 with ported head, SERT cams, race carbs, race exhaust etc it's just had it's 5000 km service with no teeth in the oil pan yet. 

I always use the clutch and am not always thrashing it but i'm guessing it's a healthy engine pushing well over 150 ?

Like @Nik(although less mileage ridden) i would not want a 5 speed anymore nor a stock 1127 either come to think about it

 

Keep us updated with reliability. I have heard of high failure percentage, but I have no hands on experience on 6 speeds in 1100+ engines. Both 750 I've had worked ok.

[clivegto]

@cregnybaatt race bikes all have 6 speed boxes but I think there all 1127's.

[george 1100]

14 hours ago, clivegto said:

@cregnybaatt race bikes all have 6 speed boxes but I think there all 1127's.

Pretty sure they use billet 

[Kamikaze]

15 hours ago, clivegto said:

@cregnybaatt race bikes all have 6 speed boxes but I think there all 1127's.

 

1 hour ago, george 1100 said:

Pretty sure they use billet 

All the classic suzuki TT bikes and most privaters use Nova 6 speed close ratio boxes, completely different to a std 6 speed box, i wanted one for my race bike....but cant afford the 2.5k they want for it..

[dupersunc]

Pretty sure Cregnybaa uses the suzuki box.

Classic team Suzuki do for definite use the Nova box..

[clivegto]

28 minutes ago, dupersunc said:

Pretty sure Cregnybaa uses the suzuki box.

 Yea I thought he did that's why I mentioned it and linked him in my comment but I have noticed he hasn't been on hear for a while. 

[Gehr]

F

 

Edited March 30, 2022 by Gehr
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[canamant]

I've just put the phone down to  Creg Ny Baa.  The reason he doesn't post here now is that he's lost all his cookies and  therefore his passwords.  Compounding this he's changed internet providers so can't get access to  his old e:mil address to renew his password.  Can anyone help him out ??