750 Triple Tree

When I fitted Yamaha 600 forks to my 920, I wanted to keep the trail the same as the original 850 yokes, & found that late model BMW K75s yokes would fit the bill. These have the 41mm bore to suit the forks & a 2 1/4" offset, which combined with the 28 deg head angle & 19" wheel gives around 4" trail. Handles fine.
 
From the Trident T150 manual ('positive' and less than one degree so unlikely to be noticed):
750 Triple Tree

Edit: That drawing is also in the pre-OIF T120 manuals.
 
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Thanks LAB. Saved me going into the workshop!

If you have an Internet connection then you are never very far from workshop manuals. ;)
Just a couple of examples:
 
If you have an Internet connection then you are never very far from workshop manuals. ;)
Just a couple of examples:
Yes I've used that previously but completely forgotten about it. Thanks again for jogging my memory. Are you aware of any similar sites for other makes?
 
Are you aware of any similar sites for other makes?

Could you possibly narrow it down a little?

Put make, model and "free manual" into your browser search if you are looking for anything specific.
Or search for "free (motorcycle?) workshop/service, etc. manuals".
Example:
 
When I fitted Yamaha 600 forks to my 920, I wanted to keep the trail the same as the original 850 yokes, & found that late model BMW K75s yokes would fit the bill. These have the 41mm bore to suit the forks & a 2 1/4" offset, which combined with the 28 deg head angle & 19" wheel gives around 4" trail. Handles fine.
WOW! I bet a 1 & only unique setup! What year(s?) yam 600 forks are the same/compatible? BMW K75 yokes from what years? Wheel info (including rear)? or any additional front end details pls?
 
I use fz750 yokes and legs on my 750
The yokes have a 40 mm offset
Handling is fine at all speeds with the increased trail
 
WOW! I bet a 1 & only unique setup! What year(s?) yam 600 forks are the same/compatible? BMW K75 yokes from what years? Wheel info (including rear)? or any additional front end details pls?
The forks are from a 600 Fazer around 2003 ish, & the yokes are K75s 1994/95, as the earlier models had 41.3mm bores as opposed to the required 41mm. The forks have been reworked by Maxton Eng. to suit me & the bike. The front hub I designed & made from a billet of 6082. The calipers are the Sumitomo type as fitted to lots of Yams usually known as blue spots. I will attempt to post some piccies in a day or two if you would like.
 
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Hi Matchless
I have a set of 41mm Minnovation forks of the shelf as per their Seeley ones. I brought them as people were using BMW forks & delugging them to make them look more classic. Never went that way in the end with the bike & ended up running 38mm Spondon forks.
Show us a photo of your bike please it sounds remarkable.
Thanks Chris
 
Not all that remarkable really Chris, but much better than the original stuff. Hope the pictures are okay as it's the first time I've tried. Please excuse all the dead flies.
 

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That advice came from the NOC Commando notes, but Andover Norton list the 850 yokes in the 750 1972 parts listing so they must know differently.

You got that wrong. Look up the frame section and you will see that the replacement frame for a '72 750 is the 850 type, hence the need for 850-type yokes.
The original frame still requires the 750-type of yokes, which are also listed.

- Knut
 
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When I fitted Yamaha 600 forks to my 920, I wanted to keep the trail the same as the original 850 yokes, & found that late model BMW K75s yokes would fit the bill. These have the 41mm bore to suit the forks & a 2 1/4" offset, which combined with the 28 deg head angle & 19" wheel gives around 4" trail. Handles fine.
We are a bit off track in this thread - I will jump on the bandwagon.

By using forks off a 1980's BMW R65 with stanchions off a R65GS, I wanted to improve my Mk3's front end. The objectives were:

* Saving weight over the rather heavy Norton fork. Stanchion diameter is a modest 36 mm, just a tad larger than Norton's stanchions.
* Stem diameter of 25mm matches that of the Commando.
* Obtaing a wider fork provides space for a double disc hub and calipers;
* Ride height at the front remains the same, thus frame geometry is unaltered;
* Bushless fork design means better slider support and low wear,
* Springing is assisted by compressed air, resulting in a highly progressive effective spring rate. (Wilbers aftermarket springs offer an initial spring rate 6.5 N/mm. not far from that of the Commando.)
* In combination with a 18" front wheel, a trail of 103mm is achieved, which is identical to the trail of the Mk3 according to my calculatiions.

- Knut
 
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I have found th3 trail is difficult to measure ,but I think on my Seeley with 53mm offset, it is near 105mm. When I was using the Ducasti 450 fork yokes with about 65mm offset, I think the trail was about 95mm. The bike mis-handled badly, and it came from nowhere. As I was braking, I used to feel the bike trying to become more vertical. With less offset, it just tips in easily and stsys more vertical when I accelerate.
You need to be very careful if you change the yokes. The bike can behave well, then suddenly frab you by the throat. The main thing is to be prepared for the unexpected. Especially the first time you ride the bike after the change.
 
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