Marzocchi triple clamps that have less standard 45mm

KERMIT1200

KERMIT1200

Hero member
Location
Worcester,UK
Hi all,
Now the race season as ended, my thoughts turn to checking,servicing, replacing items.
The suspension front and rear (well the whole bike) is going to Maxton to fully service their units that are currently on the bike.
Due to the rules/regulations on what I can change etc I am forced into keeping the Marzocchi front end!
My question is does any one know of any Marzocchi triple clamps (38mm) that can offer an offset of somewhere between 35 and 40mm?

Andy
 
No idea what they measure at, but 2 options are the parallel ones used on SFC twins that apparently improved handling; don't know if that meant speeding up or slowing down the steering. And Ducati ones. A way more expensive option would be making your own. Wasn't there someone making a Magnesium racing version a while back
 
Here you go Andy. I can guarantee the stem will be too long but you may be able to get it reduced or else make a new one.

Heat the yoke carefully before removal, its prob heated treated alloy, you definitely dont want to anneal it!

Worth asking the offset and remember it'll bash your tank on full lock but any bike thief can specialise in this kind of modification.

Cheers and good luck.

 
Jota Rob said:
Here you go Andy. I can guarantee the stem will be too long but you may be able to get it reduced or else make a new one.

Heat the yoke carefully before removal, its prob heated treated alloy, you definitely dont want to anneal it!

Worth asking the offset and remember it'll bash your tank on full lock but any bike thief can specialise in this kind of modification.

Cheers and good luck.

Click to expand...
Thanks Rob, message sent to seller.
Current setup runs a longer titanium stem anyway, thanks for tip.
Andy
 
Surprised to hear you want to slow down the steering, especially on a race bike. You're basically increasing the trail. I discovered the pitfalls when I fitted 'modern' Japanese front ends to my std SF frame (but we are talking 15-20mm offsets). Combined with std long rake (28-29 degrees) it was just all wrong. It didn't work until I removed the head tube and reattached it at 25-26 degrees.
 
piranha-bro2 said:
Surprised to hear you want to slow down the steering, especially on a race bike. You're basically increasing the trail. I discovered the pitfalls when I fitted 'modern' Japanese front ends to my std SF frame (but we are talking 15-20mm offsets). Combined with std long rake (28-29 degrees) it was just all wrong. It didn't work until I removed the head tube and reattached it at 25-26 degrees.
Click to expand...
Edit: Just read your race report and can see that you have a 'replica frame' which I'm assuming has revised front end geometry. Way to go!
 
Andy, I have a set of Marzo yokes most probably off a Ducati. Look like the same as the link that Rob posted.
I brought them off Phil Todd when I first built the Motodd. As the downtubes leaving the steering head tube are angled quite wide they gave me virtually no steering lock so pretty much useless. Once back in OZ I changed them with a set of cerianis off a 3c I had laying around.
Im currently in Thailand, will be home in a couple of weeks so can measure them. Been sitting in a box for 40 years so of no use to me. Yours for the cost of postage.
Vince, the SFC Cerriani aren't a flatter offset. Its the steering stem that is parallel instead of the 1.5deg offset Laverda used on the triples.
 
piranha-bro2 said:
Edit: Just read your race report and can see that you have a 'replica frame' which I'm assuming has revised front end geometry. Way to go!
Click to expand...
First thing I did to the standard frame headstock years ago was to relign to 25 degrees. I just followed it through to the replica frame.
motoddrob said:
Andy, I have a set of Marzo yokes most probably off a Ducati. Look like the same as the link that Rob posted.
I brought them off Phil Todd when I first built the Motodd. As the downtubes leaving the steering head tube are angled quite wide they gave me virtually no steering lock so pretty much useless. Once back in OZ I changed them with a set of cerianis off a 3c I had laying around.
Im currently in Thailand, will be home in a couple of weeks so can measure them. Been sitting in a box for 40 years so of no use to me. Yours for the cost of postage.
Vince, the SFC Cerriani aren't a flatter offset. Its the steering stem that is parallel instead of the 1.5deg offset Laverda used on the triples.
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Christ thats very kind of you. My situation is the bike is off Maxton mainly for a full service on the suspension units because other than change fork oil every year, nothing else has been done. After talking to Richard at Maxton we agreed the best way forward was for them to have the whole bike, to enable them to set up their units for the bike. After informing Richard of every possible current setting, measurement he suggest it may be advantagous to change the offset of the yokes. Bike at Maxton from 23rd, and if Richard suggest that different yokes would improve the handling I may get in touch. Any idea what the offset is ?
Thanks for offer,Andy
 
Hi Andy
Don't know the offset from memory.
I'm 2 weeks from home so can't confirm.
From Phil Todd so no idea of history.
Were 2nd hand.
Being flatter and the wide frame made the steering lock fairly useless.
If you can wait I'll measure and send photos.
Cheers
 
Andy, if you've got a replica frame I'm sure scrutineers don't insist you you use standard (or Italian?) triple clamps. You can use donor clamps off a variety of Japanese bikes - for eg, I have an early GSX-R front end, 41mm, that I used for a while - the clamps were an easy fit, probably 30mm offset. Loads of Jap bikes used 41mm forks and had steerers and bearing sizes compatible with the Lav. And dead easy to sleeve down for 38s.

You can often simply press out the Marzo steerer and swap it into the donor clamps. Just a thought to broaden your options.
 
I have had that 1 1/2 degree out of parallel tree to fork tubes a few times over the years, and it's comparable to the bike's handling when SFC parallel trees are used, and I still dont get it.Which one had longer trail and therefore more stability? People love to talk up rake being critical: more rake angle = stability and less rake = less stability, but after reading Tony Foale's book, trail dimension is way more critical. Andy, what effect are you looking to improve, faster steering or more stability? BTW, are we entering the deep, dark secret world of replica frames in race bikes? I guess different race scenarios allow varieties of modifications. Mums the word.
 
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Vince said:
I have had that 1 1/2 degree out of parallel tree to fork tubes a few times over the years, and it's comparable to the bike's handling when SFC parallel trees are used, and I still dont get it.Which one had longer trail and therefore more stability? People love to talk up rake being critical: more rake angle = stability and less rake = less stability, but after reading Tony Foale's book, trail dimension is way more critical. Andy, what effect are you looking to improve, faster steering or more stability? BTW, are we entering the deep, dark secret world of replica frames in race bikes? I guess different race scenarios allow varieties of modifications. Mums the word.
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The non-parallel has more trail (the wheel is further behind the point of steering axis on the ground). Great in a straight line, but things are a bit weird when you're turning-cornering ... no idea what's happening geometrically.

Basically steeper rake increases manouverability and more trail improvers stability. Modern bikes can run very steep front ends due to major improvements in suspension technology and frame stiffness.

Long rake and lots of trail does the opposite (think Duke bevels - long wheelbase, shallow offset clamps, big trail figures, steer like oil tankers but unshakeable in a bend). So I'm thinking Andy's racer is a bit twitchy, with 25 deg rake and not enough trail (100mm seems to be the ideal).
 
motoddrob said:
Hi Andy
Don't know the offset from memory.
I'm 2 weeks from home so can't confirm.
From Phil Todd so no idea of history.
Were 2nd hand.
Being flatter and the wide frame made the steering lock fairly useless.
If you can wait I'll measure and send photos.
Cheers
Click to expand...
Yeah no problem in waiting, no rush. Thanks for offer
 
piranha-bro2 said:
The non-parallel has more trail (the wheel is further behind the point of steering axis on the ground). Great in a straight line, but things are a bit weird when you're turning-cornering ... no idea what's happening geometrically.

Basically steeper rake increases manouverability and more trail improvers stability. Modern bikes can run very steep front ends due to major improvements in suspension technology and frame stiffness.

Long rake and lots of trail does the opposite (think Duke bevels - long wheelbase, shallow offset clamps, big trail figures, steer like oil tankers but unshakeable in a bend). So I'm thinking Andy's racer is a bit twitchy, with 25 deg rake and not enough trail (100mm seems to be the ideal).
Click to expand...
Hi , Current figures are showing 90mm of trail. Personally I feel I don't need more I'd rather have it slightly twitchy , bars just starting to move, but better turn in . Fine adjustments can be made by say dropping forks down a few mm, which I've done at Paul Ricard. Andy
 
Vince said:
I have had that 1 1/2 degree out of parallel tree to fork tubes a few times over the years, and it's comparable to the bike's handling when SFC parallel trees are used, and I still dont get it.Which one had longer trail and therefore more stability? People love to talk up rake being critical: more rake angle = stability and less rake = less stability, but after reading Tony Foale's book, trail dimension is way more critical. Andy, what effect are you looking to improve, faster steering or more stability? BTW, are we entering the deep, dark secret world of replica frames in race bikes? I guess different race scenarios allow varieties of modifications. Mums the word.
Click to expand...
Hi, What I'm trying to achieve is a base level that theoratically should work. I feel I've taking things as far as I can, and now need input from someone with greater knowledge, and hopefully will agree I've been going in right directon! This is a good time due to the suspension needing servicing , and while apart ideal time to change valves, springs etc. To answer your question I'm looking for the 'holy grail' of quick steering and stable. Better lap times here we come! Andy
 
Vince said:
Tony Foal built a bike with 80ish mm of trail and vertical forks that handled fine. It looked nuts.
Click to expand...
Hi, You just can not take two factors like that , you need to consider swinging arm length, weight distribution,tyre size etc etc . Then it all needs to be done within a set of championship rules and regulations. In a way I'd would have loved to have had built a frame, possible made from alloy, that weighs say approx 8kg, coupled up to modern front end. The one problem with the 'RGS' frame/tank setup it doesn't allow you to ride the front end easily because its quite a stretch from where you sit to the bars. Andy
 
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