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The Suck, Squeeze, Bang, Blow Moderator,
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Discussion Starter #41
I found a pic on TLplanet with a rear shock similar the one you want to fit on your bike, but is a SACHS [/URL]
Cheers TLexup, I've read most of makenzie71's posts, we have similar idea's and the sachs shock looks shorter, maybe one to look into if I can't shorten the ohlins enough. If he can get his brackets looking neater and the shock leaning forward a little more to look stock then I think he may sell a few more kits :devious

Les, the 916 wheel fits the Triumph hub as you probably know and the offset is different which is perfect. I have the chain alignment to within 1mm which I can correct via a shim on the front sprocket or spacer on the rear but need the engine in first.

The 916 Marchesini wheel I'm using will need a 5-10mm spacer to align it and the locating pegs on the hub extending and also the thread and sleeve extending back for the nut as the 916 wheel hub is narrower, but not problem.
 

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the sachs shock looks shorter.
It is 300mm centres....... You will have have worked it out already that the engine case part line is the centre of the bike.

Les, the 916 wheel fits the Triumph hub as you probably know and the offset is different which is perfect. I have the chain alignment to within 1mm which I can correct via a shim on the front sprocket or spacer on the rear but need the engine in first.
Yes,i had measured up for hartrichj and sent him that pic when he was looking at the Triumph SSSA some time back.
 

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The Suck, Squeeze, Bang, Blow Moderator,
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Discussion Starter #43
It is 300mm centres....... You will have have worked it out already that the engine case part line is the centre of the bike.
I've not had the cases in but established the centre line with the stock rear wheel and arm in. The inside of the frame castings are also equal distance from the centre line. But now you said that I could establish the chain alignment without having to fit an engine just yet....:hail

The Ohlins shock is 305mm so makenzie71's must be jacked up pretty high to fit the rocker well below the top of the subframe, too much for my taste.

I run the race bike +20mm at the rear which is the template for my calcs. I will probably raise the tail to get the look I want but probably only another 20-30mm. I think the tail risers may lift it too much so I will probably machine off the tabs from the bottom of the subframe mounts and drill/tap to accept rose joints instead.
 

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The Ohlins shock is 305mm so makenzie71's must be jacked up pretty high to fit the rocker well below the top of the subframe, too much for my taste.
Makenzie is using an NT650 sssarm, which places the lower attachment for his ducati shock only ~35mm above the centerline of the swingarm. That puts the top of his shock about 40mm lower than yours with the same rear ride height, even more when he uses the Sachs.
 

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I think the tail risers may lift it too much so I will probably machine off the tabs from the bottom of the subframe mounts and drill/tap to accept rose joints instead.
:confused rose joint, rose joint, hmmmmm... (google search)... Ahh! A rod end bearing on this side of the pond! Brilliant, simple, and ADJUSTABLE!:idea
 

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...the 916 wheel fits the Triumph hub as you probably know and the offset is different which is perfect...The 916 Marchesini wheel I'm using will need a 5-10mm spacer to align it and the locating pegs on the hub extending and also the thread and sleeve extending back for the nut as the 916 wheel hub is narrower, but not problem.
Sam, are you using a 5.5 or 6" wheel?
 

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The Suck, Squeeze, Bang, Blow Moderator,
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Discussion Starter #47
I will be using a 5.5" Ducati 5-Spoke Marchesini (couldn't find a 6" cheap enough :devious )

I've spent 3 hours and half a tree in paper working out the bloody suspension ratio's :banghead

Went to my suspension guy and we agreed that the 916 Ohlins cannot be shortened enough. He offered to give me a surplus brand new Penske shock in exchange for doing his machining work for a shock dyno he's building :devious

The shock is 20mm shorter than the ohlins but only 50mm travel

If I use the Penske with the 916 Rocker and 50mm travel the bottom shock mount needs to be 85mm from the swingarm pivot to get 130mm rear wheel travel, this puts the mount in fresh air where the hole in the arm is :banghead

If I move the bottom mount to where I would like it I only get 91mm of rear wheel travel.

If I reduce the penske travel from 50mm to 40mm and mount ala TLR Ohlins with no linkage then I get my 130mm of rear wheel travel but crap low speed damping (not that it matters too much on road bike...)

So now I'm working out the calcs if I make a different ratio rocker

So much for a step by step guide, best edit out these pages until I start moving forward again :banghead
 

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The Suck, Squeeze, Bang, Blow Moderator,
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Discussion Starter #48
BTW For anybody using a sssa and planning to keep the stock wheelbase (520mm long swingarm) with a 916 shock and linkage, then the bottom shock mount needs to be 121mm from the swingarm pivot.
 

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Sorry Sam.... looks like is getting more complicated than you expect... I'm sure you'll find a set up wich fit... Don't give up:thumbup
 

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Slice out the upper plate of the Triumph swingarm. Use it's existing linkage mount bolt to carry the Ducati lower end, and weld in some bracing on the underside of the arm, below the bolt.

That would lower the mounting point of your stock Ducati rocker over 90mm (3.5"). :O
 

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The Suck, Squeeze, Bang, Blow Moderator,
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Discussion Starter #51 (Edited)
Thats one of the only two options I have left Joseph I'm affraid

Because of the height and position of the theoretical lower shock mount of the 955i arm you can't use a rocker. You need a shock bottom pivot travel of 40mm which even with a 1:1 rocker gives you 80mm of required shock compression (any less than 1:1 and the top eye of the shock is too close to the rocker pivot) This length shock cannot be fitted under the seat.

The only way to use a rocker (and have controlable low speed damping cos the shock piston travels twice a far as a direct mounted shock for the same rear wheel travel) is to do what Joseph says and lower the theoretical bottom shock mount, but this is serious fabbing.

The other easier option is a direct mounted shock.

Also occured to me that both Ohlins and Bitubo's (and probably the others) damper solution for the TLS didn't go for a direct mounted shock even though there is room. Sort of proves that the TLR Ohlins solution was not ideal. There is no progressive spring compression either (getting harder towards the end of its travel)

As this is going to be road bike only, I'm leaning towards the direct mounting option, but need to look at the posibility of cutting and re-strengthening the arm to gain access to the stock mounting point on the 955i arm :O
 

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not sure about all your packaging issues

but i can help on those upper subframe bolts

if u have (say) a 2:1 ratio at the shock
than the maximum force at the upper shock point (assuming u have bottomed out the shock and it isnt absorbing any force)
is going to be 2 times the rear wheel force

and say the maximum rear wheel force is your wieght plus the bike multiplied by some sort of dynamic load factor (lets say "2")

so assuming u are about 100kg, the bike wet is about 200kg and u have just landed a MASSIVE jump landing only on the rear wheel :laugh

that makes the force on the bolts
FORCE = [(leverage ratio)*(combined mass)*(dynamic factor)*(acceleration due to gravity)]/(number of bolts)
= [2*300*2*9.81]/2
= 5886 N

and looking in my little Unbrako catalogue the maximum shear of a M8 Grade 12.9 Capscrew is = 39.2 kN
= 39 200 N

Which should give u a Safety Factor of 6.6 or so
remember that those bolts also have to take your ass-forces and the wieght of the subframe, but i dont think it would be a big problem

also, you need to make sure the bolts are only getting shear forces
some nice big machined spacers should do the trick
if they fit nice and snug with the inside of the chassis then it shouldnt let the bolts bend at all
 

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Do it.

You know you want to.

You've already got a great shock setup in the Ducati Ohlins.

The strengthening of the 955i arm won't be as bad as you think.

The plates you'll weld in to close up the cuts can extend downward, be pierced by the linkage bolt, and be part of the lower cross-over you'll make.

You're almost there.

Do it.

You know you want to.
 

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...I'm lost here but you might try PM'ing TLDV8 for some more ideas about your setup?...
 

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The bare TLS arm (no rear axle, pivot axle, adjusters, calipers, caliper brackets etc.) is 5.4kg or ~12.0lbs.

The bare 955i arm (WITH the eccentric hub, but no spindle or anything else) weighs 6.9kg or 15.4lbs.

So, about 3 1/2 lbs heavier for the Triumph. Of course you'd have to put everything on both arms to get a truly accurate comparison.

Also this doesn't take into account the (probable) weight loss with the Ducati/Ohlins suspension versus the stock dumper asssembly, the 5.5" wheel difference, possibly lighter aftermarket caliper setup, or the weight difference between a 190 and a 180 tire...

Going to a 520 or 525 chain size, Sam? There's a few less ounces as well.:thumbup

By the way, the 955i's eccentric hub weighs 1.2kg or ~2.6lbs, so the empty arms are within a pound of each other.:hail
 

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I will be using a 5.5" Ducati 5-Spoke Marchesini (couldn't find a 6" cheap enough :devious )
BTW, as you know, a 6" wheel would need a thicker spacer plate between the 955i spindle face and the Ducati wheel in order for the rim lip and tire to clear the inner face of the sssarm. That would require the entire sssarm be offset even more to the left of the bike, making your fitment that much more difficult (or impossible).

:banghead
 

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The Suck, Squeeze, Bang, Blow Moderator,
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Discussion Starter #58
The subframe bolts are M10 Fimp and I will be making double side plates from the rotary damper mounts aswell to beef it up. I'm glad I'm not bringing physics and forces into the equation, although I loved Physics at school and even chose it for one of my O Level exam subjects it's all forgotton now :laugh

I woke up this morning deciding to go for the direct mount option as I get a free shock out of it and can resell the 916 OHlins, but Joseph has got me looking again and cutting out a section of the arm.

I will need to through in a set of crankcases and rear cylinder to make sure I'm OK with the rear exhaust pipe on full travel etc and how deep I can make the bracing etc

Looks like I will be sticking with the 5.5" rim, but once the offset is established I will know for sure about a 6" option.
 

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...I'm lost here but you might try PM'ing TLDV8 for some more ideas about your setup?...
I have posted more than enough information and pic's over the last 2 years to show what is needed.Not forgetting i am now no longer a contributor to the TL community :O
As said before i will not post detailed information as there are people on this site who would use it for monetary gain.That goes for TB information also,saying do not bore the lower diameter was a clue in itself.

Sam will have no trouble figuring this install out.
 

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Discussion Starter #60
Had another long conversation with my suspension guy.

Ohlins introduced a double piston damper for direct non linkage applications to help with low speed damping problems.

The Penske unit that I have has a progressive piston in it which is better than the ohlins double piston solution (Mind you he would say that been a Penske agent :devious )

In view of all the extra work to persevere with the 916 Rocker arrangement and the fact it is only a road bike, I'm going to go down the direct mount route. Also I'm a little sceptical about major cutting and reinforcing of the stock arm and problems associated with distortion when welding etc, sorry Joseph :devious Also the 916 Shock would run very close to the rear exhaust pipe which in itself isn't ideal.

The penske shock will be better than a TLR Ohlins solution and no doubt more than adequate for the road.

Without the rocker I will have more room for the tip over sensor and other bits that would otherwise need moving and alternative fuel tank mounting hinge postion etc

I will need to reduce the Penske shock travel to 40mm and that will give me 130mm rear wheel travel with a ratio of 3.25:1 which is similar to the CBR600RR's and most other modern bikes which are at 3:1. I just won't have the progressive nature of these bikes and may have to look at a progressive spring instead, but thats a few months down the road yet :laugh

Thanks guys for the debates and idea's, enough paper work, time to get dirty again.......

BTW Joseph and Mackensie are using the NT650 arm which although 25mm longer fits much easier and allows the 916 rocker due to the lower bottom shock mount.
 
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