YZF750 triple tree mod questions

[Elimax]

Hi folks…I’m hoping for someone’s help here.

I’m in the middle of attempting to adapt the YZF750’s front forks and triple tree to fit on my 1986 FZX700 Fazer, and I’ve run into a problem. Here it is:

Although the triple tree’s center shaft is the same diameter as the Fazer’s (meaning the steering head bearings won’t have to be changed), the shaft is approximately 1 inch too short to accommodate the bolts that tighten back onto it after it goes through the steering head of the frame and the bearings placed in.

So my next attempt was to take the YZF triple tree into a machine shop and have them attempt to press out the center shaft from it so that we could then press in the FZX700’s shaft. But unfortunately, they didn’t have enough weight to do so, and they said that even if they did, they’ be too worried to try because of fear of breaking the wimpier metals into which the fork tubes go.

That leaves me in a difficult spot: To either go to a shop that has a stronger press and risk breaking the triple tree, or to somehow shorten the frame steering tube so that the shaft will have enough available length to be bolted back on (a process I am completely unfamiliar with.)

My hope is that one of you out there will have ideas on how I can address this, or may know of another triple tree that will hold the YZF750 forks while having a longer shaft to go through the steering head of the frame.

Thanks, folks!

Aaron

Phoenix, AZ

[rf9rider]

Did the shop heat the shaft before trying to press out the stem?

I know a lot of people who have had the stem pressed out when changing from YZF750/FZR1000 forks to R1 forks, never heard of anyone having one break yet.

Maybe you could ask around for other Yamaha triple tree measurements, FZR, R1, R6 etc?

[golfdub]

yea was gona suggest the same as rf....heat it up and the stem should pop out easy enough....if that dosnt work take the measurements ...fork leg diameter and so forth and see if any rom another bike may fit i've used ducati yokes a few times in the past with yamaha usd's they go straight on no probs

[Elimax]

Thanks golfdub and rf9rider for the help!

I wonder why heating up the stems would help? I thought that, physically, heat would expand the metal, thereby making it more difficult to remove...wouldn't cooling it way down (thereby contracting/shrinking the metal) make it easier?

Anyway, I just don't have any good way of finding out the steering stems on other bikes' length and diameter, so...I'm kinda outta luck in that area, at least for now. Lemme know, though, if there's a good way of finding out this data. That would be great.

Thanks again.

Elimax

[rf9rider]

The triple trees and stems are made out of different metals, so when you heat them up, they expand/contract at a different rate.

The trees are softer, so will expand first, making it easier for the stem to be pressed out.

Try searching for other Yamaha forums, you`ll usually get all the help from there.

Heres a couple to start you off.

http://exupworldwide.com/forum/

http://www.exup1000.co.uk/phpBB2/

[Elimax]

Excellent! I will do that....and thanks for being helpful.

Thanks agin,

Elimax

[Madison Motorsport]

What the smeg is a 'Triple Tree'?

I presume you are referring to either the upper or lower yoke?

[rf9rider]

What the smeg is a 'Triple Tree'?

I presume you are referring to either the upper or lower yoke?

Correct!

Its an American thing.