Swing Arm Conversion again!

[Albie]

I think you will find you can use the standard swingarm pivot spindle if you dont want to use the s4r hangers. They are only longer to have a thread to bolt them onto. You can reuse the circlips if you haven't damaged them of your old swingarm.

Thanks Abbe, you just saved me a couple ££'s and time. I see the circlips from the 620ie have the same part code.

The swinging arm I've got is covered in brown primer.............. I'm thinking of going back to stand metal finish. I feel red would might be to much with red wheels (still to buy)

I guess this is going to need alot of elbow grease and a few bit of sand paper to stip, maybe aluminium polish too?. Or should I wait and get it blasted when I go to get a rear wheel powder coated?

[slob]

Originally Posted by Panther

The swinging arm I've got is covered in brown primer

it's not magnesium is it?

[Albie]

No I dont think it is magnesium. It sounds like the one I got offered as a spare from Sean . It looks flesh colour primer. Personally Panther I would either as JMO may say get it polished or get it powdercoated and they will automatically shotblast it anyhow. I was going to do mine red not senna tomato red. The wheels do look ok the same colour but I nearly went satin black which is quite a cool look.

If I can save you a few pounds that good.

Originally Posted by Albie

...Personally Panther I would either as JMO may say get it polished or get it powdercoated and they will automatically shotblast it anyhow...

Hee hee - polished looks fantastic, but the S2R shape swinger would be even more of a bitch to keep clean...

Personally I'd get it shot blasted, then painted/powder coated in the some colour as the frame - whatever that is/the could you decide to do it...?

xxx

[Albie]

Originally Posted by JMo

Hee hee - polished looks fantastic, but the S2R shape swinger would be even more of a bitch to keep clean...

Personally I'd get it shot blasted, then painted/powder coated in the some colour as the frame - whatever that is/the could you decide to do it...?

xxx

They are actually very hard to clean as nooks and crannies.And a not the smoothest of castings either as my powdercoater told me. Im actually glad M1100 one is satin black. Hides a multiude of grease specs.

Originally Posted by Panther

below you see hub for 748 and S4R have a different part number

The difference in part numbers could be the bolts...
The S4R hub (part 13) looks like it comes with 3 different bolts (11, 14 and 19), whereas the 748 hub has the same bolts. but they don't come with the hub...

Also, regarding the picture/diagram of the swingarm you posted up - be careful trying to use the original swingarm pivot bar - yes the circlips might be the same part number, but the 620/750 bar won't have the chamfer for the bolt 6 and nut 7 to lock it onto - so the whole swinger would onyl be hled on by the circlips - which is probably not a good idea!

Obviously when you use the S2/4R hangers and end bolts, these offer additional security with the flange on each end of the bolts in the hanger...

The Febur kit uses the original M620/750 pivot bar, but it also clamps around each end of it like the original double sided swingarm does... the S2/4R swinger has no clamps, just that wedge bolt, which is supplemented by the end flange bolts in the hangers.

I think you'll need the the correct S2/4R pivot bar, and to be honest - it's safest to use the S2/4R hangers and bolts etc, or some fancy billet alternative for the same bikes...

xxx

[Albie]

Originally Posted by JMo

Also, regarding the picture/diagram of the swingarm you posted up - be careful trying to use the original swingarm pivot bar - yes the circlips might be the same part number, but the 620/750 bar won't have the chamfer for the bolt 6 and nut 7 to lock it onto - so the whole swinger would onyl be hled on by the circlips - which is probably not a good idea!

Obviously when you use the S2/4R hangers and end bolts, these offer additional security with the flange on each end of the bolts in the hanger...

The Febur kit uses the original M620/750 pivot bar, but it also clamps around each end of it like the original double sided swingarm does... the S2/4R swinger has no clamps, just that wedge bolt, which is supplemented by the end flange bolts in the hangers.

I think you'll need the the correct S2/4R pivot bar, and to be honest - it's safest to use the S2/4R hangers and bolts etc, or some fancy billet alternative for the same bikes...



xxx

Jen
thats all that holds all monsters together. They have plastic bungs. Dont forget that they have clamp bolts too.

Originally Posted by Albie

Jen
thats all that holds all monsters together. They have plastic bungs. Dont forget that they have clamp bolts too.

Yes - the double side swingarms clamp around the bar at each end with a slit and a pinch bolt, with a good inch width of metal all the way around to grab the bar.

The S2/4R swingarm doesn't have the slit/pinch bolts on each end - it's just a solid hole through the casting, and a single wedge bolt (single) part 6 & 7 locks the position of the bar... however, one presumes the flange on the end bolts is to to stop it sliding out either way incase that little part 6 bolt ever broke/fell out, as I doubt the circlips would hold up for long cranked over through Gerrards for example?

xxx

Interesting thoughts on the hangers end bolts (special scew, as named in the pats list) to support pivot bar. I could make some bolts and flange if needed, (small ones so they would not stick out so far). Or even drill a second pinch bolts hole in the swingarm
-I think the pinch bolt is just to stop pivot bar rotating and wearing the swingarm as there is bearing inside engine hole. And the circlips are there to stop the pitch bolt falling out due to vibration, even going round a bend I don't think there is much sideways force on them, as the bike is in balance (centripetal force)???

One of the reason why I was thinking of using 'ie' rear set,is because of the existing hanger bracket on the frame, which would be redundant otherwise.

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It sounds like the one I got offered as a spare from Sean . It looks flesh colour primer

thats the one! The casting are definitely not the smoothies too. I know Capo did alot of work on his, grinding and sanding to make it smooth.

I think you guys are right, power coating is the way forward Satin black looks good, but I don't think it goes with my colour scheme, maybe a satin grey or titanium to compliment the frame.

I'm thinking of powder coating the rear sprocket flange red too.

If I had alots of time on my hands I would probably go for a red frame and swingarm and grey/black wheel......(a mod for next year )

Originally Posted by JMo

Also, most 916/998s etc ran a 525 pitch chain and sprockets, so you'll need to factor in a 520 rear chainring (expensive - I'd get the Renthal combo). Alternatively you might be able to run a 525 chain and front sprocket? - but not sure the chain will line up on the swingarm slipper - not sure if the S4R runs a 525 or 520 chain like the S2R?


xxx

I've already got a DP 43 rear sprocket from Cappo's S4R, which is a 525 pitch. There for I'm guessing it will line up with the swingarm slipper. Does this mean a 525 Chain and Renthal front sprocket should complete the job nicely.

Originally Posted by JMo

You will also have to bare in mind that the speedo pick-up requires 6 pulses (bolt heads) for the regular swingarm ie monsters (inc the S4), whereas I believe the S2R/S4R only needs four pulses/bolts... on my Febur conversion kit, they mod the stock 916 rear disc with tabs to correctly space six ferrous bolts to drive the speedo pick-up.

xxx

TBH, I don't know much about my speedo pick-up, and the modding involved to make my speed work. I hope it all becomes apparent when I get to it.


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I've finally got myself a rear Marchesini 5 spoke wheel from Italian Ebay, I paid a little more than I wanted to, but needs must! Hopefully it should not take to long to arrive so I can get it and the swingarm powercoated.

JMo my bikes been kept in a garage away from my home, but I finally understand exactly what you mean regarding the speedo pick up, With my bike having 6 pick-up (bolt heads) where the rear disc it attached, and a S4R has 4 bolt heads.
Hopefully my farther can reprogram the input signal to be multiplied by 1.5 (=6) Otherwise, I'm looking at adding 2 dummy bolt heads but as they would not be evenly spaced, I guess it would make the speedo go a bit 'wavey'.



I though I would also post a few pictures of poor casting. Today I decided to spend an hour sanding the on worst area's. The who swingarm is going to blast and paint soon anyway.

'flesh colour primer'




Close up




15mins later


end result- it's not perfect but I think it will look good after blasting and painting

[Capo]

The swing arm is made of two basic components the front is a casting and the rear appears to be an extrusion.
Heres mine after much filing to remove all the casting flash.





The finished item

Now that's a proper job!

I really like it how you have removed the beading, on the bottom part of the swingarm, it really cleans up the lines. I don't think I have the patients to remove it and could very easily f* it all up!