Reducing front wheel lead

[fredintoon]

I got a PM asking about what I did to reduce the front wheel lead (move the wheel forward) to lighten the steering on my XS650/Velorex sidecar rig.
The short answer is I didn't feel the need to do that on this rig because it steers OK as is.
But here's the same el-cheapo way to do it that I did on my XS11 rig if you do feel the need to modify an XS650.
For an XS650 you need to find used front end parts from a Standard AND a Special XS750/850/1100. Any of those models will work.
It takes the long series triple trees form a Standard mix'n'matched with the fork legs from a Special. That combo reduces the lead by ~40mm.
The only mechanical difficulty will be fitting the XS750/850/1100 triple trees into the XS650 frame and the list's search button will help you there.
When the Standard 'trees are in the frame the Special fork tubes will bolt right in.
The appropriate fork tube diameter ears will fit the 'trees but I dunno about the length being right. You'll have to check that on assembly and trim or make a spacer if required.
Along with the Special fork legs you'll need the Special's fender and alas you will be stuck using the Special's Weird Harold front calipers.
Note that XS750/850s use the same smaller diameter brake disks as the XS650 rear brake while the XS11 uses the same diameter front disks as the XS650 front and later model XS11s front disks are slotted so you don't have to drill them.
BTW ALL XS650 Disk brake fronts after '73 will fit in ANY XS750/859/1100.
Your cost in used parts for this should be less than $200.
Next least costly steering lead reduction is a SteerRight conversion at ~$900 or a leading link front fork at over $2,000.

 

[650Skull]

Note that XS750/850s use the same smaller diameter brake disks as the XS650 rear brake while the XS11 uses the same diameter front disks as the XS650 front and later model XS11s front disks are slotted so you don't have to drill them.

BTW ALL XS650 Disk brake fronts after '73 will fit in ANY XS750/859/1100.

Bit confusing

Rear disc brake rotors from 78SE/79SF/80SG are interchangeable with XS750/XS850 Triples.

Some, if not all Euro front rotors from 77-82 had the smaller rotor mounted to the front forks and these can be interchanged with the 750/850 front and rear rotor

Front Rotors from 77D and later models are interchangeable with XS1100 front rotors.

XS650, 73-76, front rotors have a different profile to the later, 77-82 front rotors, so can't be used on an XS1100. Maybe the earlier 73-76 rotors can be used if the caliper from 73-76 was used in conjunction with the early rotor. Don't know if the XS650 73-76 caliper is interchangeable with the XS1100 fork

 

[gggGary]

AFAIK the XS750 fork legs were 35mm in 77 and 36mm after that. So watch your years if you're gonna start swapping dis and dat. I think the XS750-850 tubes are about an inch longer than the Xs650 tubes.

 

[fredintoon]

Hi Garry,
were they so? I only ever worked on a '78.
That means a '77 XS750 Special's fork tubes will fit in a '77 or later XS650's trees to give that lessened trail, right?
Still need the XS750 Special's front fender though.
And yeah, you always gotta be careful swapping stuff.
Mr Caliper is your friend, eh?

 

[gggGary]

Nah, I wus wrong, turns out it was just something I recently saw (and just verified it's listed there) on MikesXS (motto what could go wrong?) then I went and looked at the real Yamaha parts lists, they show all the XS750-850 were 36mm

The XS1100s are 37mm

1KH-23145-00-00 OIL SEAL is used on these models and components:

1977 XS750-2D FRONT FORK (XS750-2D)
1978 XS750E FRONT FORK
1978 XS750E_227 FRONT FORK
1978 XS750SE FRONT FORK
1978 XS750SE-31 FRONT FORK
1979 XS750F FRONT FORK
1979 XS750SF FRONT FORK
1980 XS850G FRONT FORK
1981 XJ750RH FRONT FORK
1981 XS850H FRONT FORK
1982 XJ750RJ FRONT FORK
1982 XV920J FRONT FORK
1983 XJ750RK FRONT FORK

37mm



1978 XS1100E FRONT FORK
1979 XS1100F FRONT FORK
1980 XS1100G FRONT FORK
1981 XS1100H FRONT FORK
1981 XV920RH FRONT FORK
1982 XV920RJ FRONT FORK
1983 SECA - XJ900RK FRONT FORK
1983 XJ650LK FRONT FORK

 

[nj1639]

AFAIK the XS750 fork legs were 35mm in 77 and 36mm after that. So watch your years if you're gonna start swapping dis and dat. I think the XS750-850 tubes are about an inch longer than the Xs650 tubes.

'77 xs750 Standard (non-leading axle) are 36mm and about 1 3/4" longer ;-)
'77 may be the last year for the non-leading axle in the xs750.

Xs650 front fenders, special or standard, will swap right over to the standard xs750 forks but won't for the xs750 and xs850 leading axle forks.

 

[650Skull]

Doesn't have the XS750D on that list. I looked it up, and it doesn't show the XS750D oil seal matching to any other XS750/850 nor an XS650 but it does match up with some XS500's ??

 

[gggGary]

I don't find any XS750D just the 2D?? What's the difference?

OK found it, details here. https://en.wikipedia.org/wiki/Yamaha_XS750 So I guess mikeXS may have it right after all, there may be some 76-early 77 750's with 35mm tubes??? I'm dumb about the 750's will probably stay that way.

 

[weaselbeak]

I have an early 750 front fork setup here somewhere, and I know it is at least 36mm.