Bandit Coil Spring Conversion

Words & pics: Lee Workman

Bandit clutch conversionBandit Clutch

The clutch assembly fitted to all Bandit 1157 motors is, frankly, shite.

Based on the same principle as the GSX-R Slingshot unit, it’s diaphragm-sprung with ten driven plates and ten drive plates of 225mm diameter (the GSX-R’s are 230mm diameter which doesn’t sound much, but offers a huge increase in surface area for friction) and has a cheap cast alloy basket with a steel reinforcement strap fitted in an effort to stop it flying apart (as opposed to the large all-steel basket used in the GSX-R).

Under normal circumstances this unit is fine but, as soon as you start giving it a reasonable amount of abuse or tune the engine, it will struggle to cope with the extra demand and eventually slip. Heavy-duty diaphragm springs are available and will slightly improve matters at the cost of a heavy clutch lever, but the whole unit is better off in the bin. Trust me …

To convert your Bandit 12 clutch you’ll need the following parts from Suzuki,

No. Description Suzuki Part Number

Qty

Price � (ea.) Source Model

1

Clutch inner hub

21410-06B02

1

49.46 GSXR1100 G,H & J

2

Pressure disc

21462-06B00

1

23.49 GSXR1100 G,H & J

3

Coil springs

09440-20013

4

1.31 GSXR1100 G,H & J

4

Spring spacers

09180-06174

4

1.72 GSXR1100 G,H & J

5

Washers

09160-06020

4

0.53 GSXR1100 G,H & J

6

Bolts

01107-06307

4

0.71 GSXR1100 G,H & J

7

Drive plate (Fibre)

21441-48B00

11

9.53 All GSXR 1100’s

8

Driven plate (Steel)

21451-48B00

10

5.47 All GSXR 1100’s

9

Clutch Basket

21200-40814

1

176.53 GSXR1100 K,L,M & N

Yep, you’ll need to replace that crappy clutch basket, they are expensive new, but you could get one from B12 Clutch 1a breaker, you can use one out of any Slingshot model. Beware – they look identical to the earlier Slabside one, but the 1052cc motor has different gearing on the crank. The primary driven gear at the back of the clutch basket of Slabside engine has 73 teeth. The bandit primary driven gear (being essentially a 1mm over bored 1127 motor) has 72 teeth – the same as a slingshot one.
Follow the previous instructions for the GSXR’s then, once the inner hub is completely off, remove the outer basket also.
Pull the basket partially out, then push it back in again, this will expose the needle roller bearing and the spacer, remove these from the shaft then remove the clutch basket and alternator/oil pump drive gears careful remove alternator oil pump gear from the b12 basket and fit it into the slingshot basket
If its still stuck to your clutch basket, you will need to (carefully) remove this bandit drive gear, and fit it to the GSXR basket.
They are totally different; the alternator/oil pump drive gear off a GSXR has different pitch teeth and will foul your bandit alternator driven gear and your oil pump driven gear.

Once you’ve done this you can fit the new GSXR Basket using the original thrust washers in their original places.
Ensure the alternator an oil pump drive gears are engaged with the driven gear behind the basket
When positioning the basket on the counter shaft and sliding it ‘home’ – take extreme care to line up the alternator/oil pump drive gears with the alternator and oil pump driven gears, if they are not fully engaged, and you tighten the hub nut, it WILL snap, and they cost around £80!

Fit the new coil spring hub assy just like the GSXR procedure with one exception, –
The counter shaft of the bandit engine is again longer than the Slabside one, but it’s different to the Slingshot counter shaft, the dimensions for the bandit spacer are 35mm O.D, 25.5mm I.D and 6mm thick. Also as the original bandit hub has a different thickness base to either of the gixxers, it still works out that you need a 10mm ball bearing to take up the slack between your original bandit pushrod, and your push piece.
Again secure the hub using your original nut & washer on the new spacer fit the new GSXR clutch plates and pressure disc assy as above.
And you too have a GSXR spec, coil spring clutch!, Again you can go and fit a lock up straight on if you wished!, Or leave it as it is and go and do stoopid stuff, safe in the knowledge that you’re clutch can take it!
Now, extra hints and tips.
Tip 1: When you do the job, put the bike on its side stand and carefully lift the front wheel and chock it on a brick – this will stop you losing any oil when you remove the clutch cover.
Tip 2: When buying new clutch plates, use only genuine Suzuki parts – I know they’re more expensive, but it’s false economy to put cheapo plates in. I know, I’ve tried ALL the super-trick/heavy-duty ‘performance’ clutch plates and they just don’t compare with the genuine stuff. You have been warned!
Tip 3: With this particular conversion you fine-tune the biting point by changing the ball bearing – if it drags too much (assuming you’re using the correct grade oil and the steels aren’t warped), then you need more travel so try fitting an 11.5mm one instead. If it slips (assuming the fibre plates and/or the springs aren’t worn), you need less travel so pop in a 9mm one. It really does make a difference!

Also take the time to make the special tools, they’re a piece of piss to make, and really make life easier.

Special tool one: You’ll need two pieces of steel bar that are 200mm long, 25mm wide and 5mm thick (ish …), drill two 6mm holes in each bar with the centres 165mm apart then, at one end of each bar, fit a M6x30 bolt and secure it tightly with a nut on the underside. At the other end, open out the 6mm hole to 8mm and join the two bars together with a M8x70 bolt and loosely secure it with a nut on the underside. To use it, the M6 bolts will neatly fit into the slots on the diaphragm pressure disc and the M8 bolt will fit straight into the swingarm spindle – once the slack is taken up, you’ve got both hands free to undo/tighten the big 50mm holder nut!

Special tool two: First get one 400mm long piece of square section (20x20mm) bar and two old GSX-R clutch driven (steel) plates. Put the plates on top of one another and drill three holes equally around the diameter and secure them to the square bar using two M6x60 bolts and 20mm spacers and a couple of M6 nuts (this way, you can support the basket really well and reduce the chances off slipping, as the plates will be deep inside the unit). Finally put a small M6x10 bolt and nut through the remaining hole to secure the plates together. This is a wicked tool to have, when you’re trying to remove/secure the hub nut at 160Nm!

Anyway, in preparing this article I’ve been down to my local Suzuki dealer to get the correct part numbers for you to order and latest prices (all, are + v.a.t.,and correct at August 2002), and to ensure that those of you using second hand stuff from the breakers get the right bits off the right models. I’ve already checked to see which part numbers are superseded by later ones and that the information given is correct to the best of my knowledge and experience etc– aren’t I good to you lot, eh?

GSX-R engine mounts for GSX frames.

Below are drawings of engine mounts to fit an early air-cooled GSX (round frame tubes) or EFE (square frame tubes) with a GSX-R engine. Both place the engine in the middle which is aesthetically best but may cause some problems with the exhaust headers interfering with the frame downtubes, which can be solved by using spacers or modifying the headers if necessary.
Engine mountsEnginemounts1 for a GSX1100 frame to take a GSX-R engine.
By “jonboy”

 

 

 

 

A Katana with the above engine mounts installed…

katanagsxr3

 

 

 

 

 

 

 

Engine mounts for a GSX1100EFE (GS1150) to take a GSX-R engine.
By “GJG”

Below are drawings from the engine mounts, as I used them a few years back. I built at least two EFE’s using these plates. They mount the engine pretty straightforward, like in the Katana I send you pics from a few months back. I also included the cutting contours in .dxf format, that could straight be fed into a laser.

Parts description:
PL-105 and 106: Take front rubber engine mount, and lower below crank. Need shims or bushes to compensate for offset.

PL-107 and 108: These should be welded in with the engine or cases in place, mounted with the previous mentioned plates. PL-108 is a bit long, and could do with a brace, taking sideward loads to the cross tube from the shock. The stock plate should be removed. The lower cross tube in the frame will need some cleaning up and removing of the stock lower rear plates, before taking PL-107.

PL-110 and 111: These make the removable, welded upper rear engine mount taking loads to the stock bolt holes/bushings welded into the side of the frame.

GSX1100 Laser drawings

Making your GSX frame stiffer

Making your GSX frame stiffer
Written by Mr.7/11, inspired on earlier work done by Tony Foale, Arnout and Tinus.

It may be well known to anybody that creating a stiff frame has to do with connecting the headstock to the swingarm pivot as direct as possible, which is what modern “Deltabox” frame designs do. So the best possible solution is to weld f*cking huge bars from the headstock directly to the swingarm pivots. There is just one problem with that… there’s a huge mother of an air-cooled engine in between that hasn’t followed any diet …ever.

frameremovals

To keep the weight down we remove some before adding any.

And besides she’s so beautifully shaped that we wouldn’t want anything hiding those luscious curves from full view now would we? So we’ll have to resort to beefing up the frame we have as well as possible so the front wheel will keep in line with the rear during heavy braking/acceleration as well as big bumps in the road.

The GSX frame is of the “cradle” type which means the main frame tubes are routed above and below the engine. We haven’t got many options for reinforcing the lower cradle as there are exhaust pipes, oil cooler lines and the oil sump between them and we don’t want to create problems while performing regular maintenance.
So we leave it alone with it’s primary task to keep the engine in place concentrate on the part of the frame that runs above the engine.

Take a look at the picture below.
The weak point of the frame is the green section between the headstock (yellow) and the swingarm pivot area (blue). If you look at early GSX-R frame designs you see that on race bikes they have allways tried to beef up that area with additional plates. There’s also a rumour this is what Yoshimura used to do with their GSX superbikes.  Suzuki have allready paid lots of attention into making the headstock as stiff as possible so the effect of additional bracing here will be minimal. If you intend too keep the standard airbox and the battery in it’s original place then options for bracing around the swingarm pivot will be minimal too. So if you would like ot improve the stiffness of your old dinosaur I’d make modification C. first, and consider dumping the airbox in favor of separate K&N filters to be able to add D. and E. When you’re at it you might as well go along and add braces A. and B. but I don’t consider them to be essential.

Be warned that reinforcement C. can hit the inside of the tank if you make it too big and will also make it hard to find enough space for the air filters! You should make all reinforcements from cardboard first anyway to check that they don’t interfere with anything.

framemods

A. these tubes support the headstock against torsional movement. The plates B. support the frame tubes to prevent them from bending due to the load created by tubes A.

The cross-bars D. stiffen the area above the swingarm pivots. The tube connecting both sided is placed at the same height as the engine mounts to keep the engine in place under acceleration. If we replace the cross-bars with a pyramid D1. we add even more stiffness to that area and prevent the swingarm pivots from moving back and forth in addition to up and down. It may look a bit awkward and I question if it adds anything as you must not underestimate the strength and function of the rear subframe.
This might be why Yoshimura adds gussets to the subframe on the Katana 1135R, but they have also changed position of the shock mounts considerably. They probably did this because they use a very short swingarm to decrease the wheelbase and so improve steering into corners and if they kept the original mounting point the shock would be too upright making them too hard.

framebraceexample

Examples of frame braces on the Yoshimura Katana 1135R

The connecting rectangular tubes E. help to distribute loads from the swingarm pivots to the rear of the frame, as well as providing a mounting point for the rear brake amongst other things.

F. There’s very little room to triangulate the space in front of the cylinders because of the exhaust pipes but it is possible. You may need to dent the tubes a little to make them clear the exhaust pipes but this is better than making the V smaller. Tightening the two center exhaust clamps will prove difficult too.

Gussets © Tony Foale

Gussets © Tony Foale

Now that the headstock and swingarm pivot areas are beefed up the connecting tubes are supported by plates C.

You should also consider making B. and C. box sections, so placing a plate on both sides of the tube with a strip in between to close the box. Or use rectangular box-sextion like I did (60×20)

Tubes only need to be around 16mm in diameter with a 1mm wall thickness. Box sections need to have 1mm wall thickness and single gussets 3mm.

Below are images of a braced GSX1100S Katana frame.
The bracing is designed by Mr.7/11and welded by Postma Motoren from Haarlem (NL)

Usually I don't get horny from stiff objects but this is a completely different matter...

Usually I don’t get horny from stiff objects but this is a completely different matter…

You can allmost feel the flow of the forces trough the frame tubes

You can allmost feel the flow of the forces trough the frame tubes

The big cross means "no airboxes allowed" and will probably be painted red

The big cross means “no airboxes allowed” and will probably be painted red

The use of rectangular beams in the subframe means it's easier to bolt stuff onto it like electronics, brake pumps, nitrous solenoids etc.

The use of rectangular beams in the subframe means it’s easier to bolt stuff onto it like electronics, brake pumps, nitrous solenoids etc.