[ksanjee]

Thought I would share this. I am unable to find an image of the rear shock rocker arm that was the most complex to design.

I produced small quantities of these parts but had a lot of different parts primarily for Ducatis. I did make rear sets for MV as well.

I finally got around to locating all the solid models. I made special triples for 1098 much better looking than the ones shown here. I am not able to locate pictures of it. They were made from 7075 T6 Al.

Krishna

[Rehaan]

Nice stuff.

There's nothing like CNC machined, anodized aluminum to get me drooling.

It would be good if you could also mention details about each piece : the purpose, and the improvements you made (whether functional or aesthetic).

cya
R

[ksanjee]

Yes indeed. I was looking for the brochures I had created but I am not able to find them.

The counter sprocket covers - 1st picture is purely aesthetic.

The open clutch cover - enables the clutch to stay cool and also sounds awesome - there were different designs to it. I have shown the most exposed and the most enclosed here. It looks much better than the stock part. I think the most enclosed one is actually PVD coated.

The rearsets (for 1098/848 and 748/916) shown are functional - allows adjustability of the foot peg and toe peg through swivel motion. For the 916, even the brackets have two mounting positions. The foot pegs come in two lengths and also have a removable end (this is used to pivot your feet for racing)

I also show a Reverse shifter (for 748/916 series) - to switch the shift pattern (racers like to bang down for upshift) - gets rid of extra linkages and mounts to the shift shaft directly

The triple clamps are also functional - I think these are 32 MM offset. I have also supplied 30 and 28s. It brings the fork legs closer to the steering stem. I have even seen 28s on some race bikes (I understood Neil Hodgson used a 26 mm offset at tighter tracks like Sears) - On race bikes you will see the settings marked on the top triple clamp and you can change it on the fly - I will share a picture Troy Bayliss's superbike when I find the picture. I will also share the resulting geometry chances for the 916 series if I can find it. In stock trip, the 916 series came with a 36 mm offset (their rakes were also adjustable through an eccentric in the steering head - so you will see two positions for the steering damper.)

I made the triples for Showa and Ohlins forks (53 and 56 mm dia.) There was quite a lot of R&D involved working with the dealer and racers. Because when you bring the fork legs closer there it can result in tolerance issues with the radiator since these bikes are built without a lot tolerance (being performance oriented) - it may look fine when it is static with the forks compressed fully. But when you are braking hard and with the forks compressed, the very slight flex in the fork legs can cause interference - I heard from Munroe motors that it actually happened when racing - don't recall what triples they were using. I also made them for 1098s - In my opinion these were the best looking parts I made. People with 1098Rs had put it on and raced with it. From a machining point of view - the bores needed to be with a few microns or they would egg-shape the forks. There was 37x1 mm threading for the stem, and other challenges.

I would love to share the picture of the rocker arm if I can find it.

More later.

Krishna

[Sutripta]

Hi,
Shifter:- how did you do the internal milling?

Regards
Sutripta

[ksanjee]

It is broached - you make a special tool for it.
Krishna

[Sutripta]

Originally Posted by ksanjee

It is broached - you make a special tool for it.
Krishna

You made a broach for a one off job!!!!

Take a look here. http://www.team-bhp.com/forum/4x4-te...ml#post3552974
You will be the hero to a lot of people.

Regards
Sutripta

[ksanjee]

I ran small production runs of 10 or 20. I may have produced around 60 or so total. The yield was low. I used to get a couple of rejects in every run because of positioning/alignment. I had designed a sprocket carrier that needed a much bigger broach - I never went through a production run.

I will look through the thread you have included...thanks..

Krishna

[Sutripta]

Hi,
Just a suggestion: In all the areas where you have machined using an end mill, cosmetically more appealing would have been to reprogram the tool path to lay down Geneva stripes. My opinion only!

Regards
Sutripta

[ksanjee]

Thankyou for the suggestion - I was not aware of this. I always had an issue with surface finish and never liked the way it came out. It was a constant struggle. Having no background in CNC machining, I was at the shops' mercy.

Anodizing is another issue on its own. I did most of it locally in California.

Krishna

[Sutripta]

^^^
Where are you based? Your profile says Bangalore.

Regards
Sutripta

[ksanjee]

I moved to BLR several years back. I live in BLR now.

Krishna

[Sutripta]

^^^
Obviously the work showcased in this thread was done in US.
If it is not an intrusion/ invasion of privacy, would you mind sharing the background to this work. Should be interesting.

The triple clamp: rigidity calculated, or empirical/ experience based?

Regards
Sutripta

[ksanjee]

It was primarily a hobby driven by my passion. It got fairly serious at one point and my weekends would be consumed completely. All holidays would also be consumed by it. During my vacation, we (me and my 6-8 year old son) - would visit dealers in California and often make a sale on the spot We would even drive out to southern California couple of times a year.

To answer your question on stiffness, my intent was not to build a stronger component. It was a consequence of NOT trying to optimize weight and strength - here you would need advanced analysis capability. The stock triple clamp is very strong as it is. They are sand-cast and for most part hollow inside with strengthening walls connecting the stem bore to the shock leg bores. These are designed with a solid understanding/analysis of the primary forces (and which planes the component needs to be strong in) - I also studied the Ohlins versions (very different approach - they have used an I-beam concept)

Using aircraft grade alum (7075 T6 in some cases) and erring on the side of caution - meant my designs would be at least as strong as the stock ones. At the same time, I could not afford to just beef up the part in the interest on making it as strong as possible (this is also undesirable)

The challenge was the clearance with the fender/radiator, position where it grabs the fork legs, positioning of steering stops, accuracy of the bores etc. These are critical structural members of the suspension and there is simply NO room for mistakes. Having fast riders who can test on the track was very helpful. Also their feedback was very valuable to get it right.

I cannot claim my triples were 30% stronger since I don't have data to back it up. I can say with a very high degree of confidence they are at least as strong for the application. We started off making it very strong and gradually, honed it down until we were comfortable. There is some common sense you can apply combined with an understanding of motorcycle suspension dynamics. I am NOT claiming to be an expert. I always leveraged the knowledge of racers and suspension experts - esp. who know the ohlins suspension inside out.

I started by looking at the blue print of ohlins forks (which I found on the web) - they indicated tolerances in microns for the bores. This was critical as well.

Hope this gives you some idea.

The rearsets is another story for another time. Will share.

My second generation triples looked completely different - based on learning from the first - I will post some CAD images.


Krishna