6speed in bandit 1200 cases

[dupersunc]

Anyone else done this? specifically the later Bandit 1200 cases.   I'm just chucking one together with a 750j/k gearbox and it looks like I need to clearance the case a little to clear one of the  gears on the first motion shaft. 

Never heard of his being necessary. Surely the internet can't be wrong?

 

[Swiss Toni]

6 speed 750 Slabbie goes into 1127 cases easily enough. Can't be that much difference internally between 1127 and B12 surely?

[dupersunc]

All works fine till I clamp the cases up the final 10thou, then one of the gears catches, and the shaft will only turn a few degrees. I'll split the cases again at the weekend when I have more time, and have proper look.

[fatblokeonbandit]

read frankinseins guide, its to do with the double row bearing, needs reversing and repinning if i read it right, was going to do this a while ago, but ended up on the "too hard" pile

[dupersunc]

2 hours ago, fatblokeonbandit said:

read frankinseins guide, its to do with the double row bearing, needs reversing and repinning if i read it right, was going to do this a while ago, but ended up on the "too hard" pile

Done that bit. Simple enough. The output shaft spins fine.

[Swiss Toni]

Could you try Engineers Blue on the gear that's catching, and,  if it's rubbing on say, a bearing boss with plenty meat on it. Could you not 'ease' the obstruction to gain your needed clearance?

[dupersunc]

20 minutes ago, Swiss Toni said:

Could you try Engineers Blue on the gear that's catching, and,  if it's rubbing on say, a bearing boss with plenty meat on it. Could you not 'ease' the obstruction to gain your needed clearance?

That's what I'll probably end up doing.

 Just currious if anyone else had encountered this. If some one has i 'll get busy with tbe die grinder and not waste any time looking for an issue that isn't  there. 

As it stands though, i need ro have a closer look.

[Swiss Toni]

It's mixed reviews on the conversion. Some say the 750 gears aren't man enough for the bigger motors, and some have had no trouble at all, after years of use. The conversion has also been used in race motors. I took my gearshaft in to work, to have it drilled for the 750 pushrod. The Turner said it would be a hard job getting a true hole through the shaft, due to the length, and tough to drill because of the case hardening!  It's do-able, but not simple!

[dupersunc]

Yeah yeah. I've read all that. I've drilled the shaft. Again that wasn't as difficult as the net would have you believe.

Not really after opinions and hearsay here thanks guys. Just someone withactual experience of doing this conversion.

[MeanBean49]

10 minutes ago, dupersunc said:

Yeah yeah. I've read all that. I've drilled the shaft. Again that wasn't as difficult as the net would have you believe.

Not really after opinions and hearsay here thanks guys. Just someone withactual experience of doing this conversion.

Ace. You tell em. Haha

[cregnybaa]

All of my bikes are 6 speed but I have not used bandit cases on any of them. just built a new big engine using 750 cases and box. I think the problem you have could be something to do with the bigger output bearing

[dupersunc]

Output shaft turns fine. I did occur to me that it's extremely fortunate that fliping the output bearing happens to locate the shaft laterally in the correct spot. It doesn't look like it's catching 2 gears and with 20 thou. Gap between cases it all turns and selects gears fine.

What clutch set up do you use?@cregnybaa

I'm looking at using a hyabusa or tl1000r clutch.

Edited September 6, 2017 by dupersunc

[cregnybaa]

I use 1052 clutch if its 1052 crank or 1127 clutch if its 1127, I must admit I have thought of using a gsxr 1000 slipper clutch but didn't  see the point in the end.

[dupersunc]

Well this has been bugging me, so instead of doing anything that might earn me a living, I spent this afternoon stripping this back down and checking every thing. Not quite sure what I'd done, but a did a dry build without crank and it all worked fine. Built it back up again now with the crank etc fitted and torqued up and all is good.

Just me being a mong.

Cheers for the help.

[370steve]

12 minutes ago, dupersunc said:

 

Just me being a mong.

 

think we have all been there at some time or other  some of us more times than others 

[canamant]

On 9/6/2017 at 7:17 PM, cregnybaa said:

All of my bikes are 6 speed but I have not used bandit cases on any of them. just built a new big engine using 750 cases and box. I think the problem you have could be something to do with the bigger output bearing

 

 

Not those shonky old things again !!

 

 

[SBK1000]

I do not know much about these engines, and I am just thinking out loud...
 
If the 750 dot heads fit on the 1100 cylinders, Is it possible to swap 1100 cylinders and pistons on a 750 bottom end???

[dupersunc]

Short answer. No.

[SBK1000]

Sounded too easy... LOL

 

[cregnybaa]

You can on the j/k  cases as they are line bored the same as an 1100 obviously you would use an 1100 crank.

[Oilyspanner]

Keep us up to date  with your findings Dupersunc - good thread, I think there's a few of us who have thought about a 6 speed box, or  closer  spaced ratios - not because the engine can't pull  widely spaced  ratios,  just that closer spacing doesn't upset the bike as much when cracking on a bit !  

[dupersunc]

1 hour ago, Oilyspanner said:

Keep us up to date  with your findings Dupersunc - good thread, I think there's a few of us who have thought about a 6 speed box, or  closer  spaced ratios - not because the engine can't pull  widely spaced  ratios,  just that closer spacing doesn't upset the bike as much when cracking on a bit !  

Will do.  Next, the clutch saga.  Looking at going down a different route to normal.

@cregnybaa

What sprockets do you run for short circuit stuff? I'm currently geared for 155mph at 10,500rpm with my 5speed.

[cregnybaa]

I.o.m. gearing is 16/42 at Aintree I would  use 15/43 Aintree is a fast track like snetterton. its a bit tight to fit a 16 but it will go.