Wheel size modifications/variations

I put 17" wire wheels and radial tires on my '73 Z1-900. Love the handling improvement this change made along with Race Tech cartridge emulators/Race Tech springs, GS1100E swingarm, and Performance Works rear shocks. But I braced the frame and used an oversize and a stronger engine bolt kit as well to go along with the above mods.

The bike certainly sits lower but I expected this. Using the centerstand can be a challenge now however.

More than one way to skin a cat... Bob brings up a another good upgrade with the close tolerance motor mounts. they take the slop out and tie the engine in the frame. Pingle has a bolt on kit. They are not too hard to make, but sourceing bolts can be tough.

The FSM has the 750h1 listed with 30 degrees of rake and 121mm trail (4.76") important to note that the LTDs have leading axle forks to help bring the trail down with that much rake. You will loose that offset as well when you go to the new fork.

also if you don't have the FSM i recommend you get it. If you need I can email.

I have a feeling I'll end up with a 19" front just to get the most ground clearance I can.

This sounds a daft idea, modern USD forks. 17" cast wheels for a cafe racer style on an Ltd?

Maybe you could find a better 750 frame as a donor bike, the GPz750 R1 a better frame all around, the Ltd variant is not really designed for fast steering.

Good advice above, you really want a complete front end, wheel ,discs , calipers, yokes etc to save a lot of other parts that won't easily fit together without expensive machining.

Some classic bikes just look so goofy with modern running gear imo

also if you don't have the FSM i recommend you get it. If you need I can email.

yeah sorry, I was looking at the trail for the 750E (which is 107mm)

17" cast wheels for a cafe racer style on an Ltd?

Sorry may not have clarified, These won't be cast, I'll be having a new pair laced to a compatible GSX-R front hub so the entire front including hub, rotors, brakes and axle will be functional together.

Also, I just ran some measurements and it appears that with the new forks and existing 19" front wheel size, trail is coming in at right at 102mm. i guess a question worth throwing our to the discussion would be is what others who have done conversions have seen from theirs in regards to the low end of trail. I know some more modern bikes have sometimes 90-95 mm of trail but that seems pretty low for a frame with as much rake as this and 121 mm of trail stock.

Remember to factor in the offset of the yoke spindle when calculating the trail, this can change by quite a lot between different models. Ultimately your real test will be the 'feel' riding it, not the numbers.

The Ltd is very conservative frame geometry, I bought one 20 years ago for a (novice rider) friend, nice motor but slow steering and goofy handling I thought. This one was a USA import, a very nice bike - just not for fast twisty roads.

As I'm 6'4 tall, all my bikes are modified with longer shocks...between 10-25mm , both my 550's run on 18" fronts. I like quick steering but nowadays rarely go over 100mph, so it is a good compromise for me. The only scary tankslapper I had, 20 years ago, was down to worn and mismatched tyres.

slc-kz wrote:
Also, I just ran some measurements and it appears that with the new forks and existing 19" front wheel size, trail is coming in at right at 102mm. i guess a question worth throwing our to the discussion would be is what others who have done conversions have seen from theirs in regards to the low end of trail. I know some more modern bikes have sometimes 90-95 mm of trail but that seems pretty low for a frame with as much rake as this and 121 mm of trail stock.

That is probably OK for trail. whats the rake? and fork offset?

Bringing this back for the dead . I jut swooped a 05 gsxr 1000 front end for my 81 kz750h. I was looking a the stewing stem conversions sold here: cognitomoto.com/collections/fork-convers...-for-fork-conversion

I'm interested in the steering stem they sell, but only see one for a kz650, I'm pretty sure it will work, does anyone know for sure?
The only reason I think it will is because when I was assembling my bike a accidentally had a set of kz650 tripes powder coated . I've Ben running a 78 kz650 front end on my 81 750h for some time now.

Any comments/ concerns?

Nice looking ride. Most guys just put the KZ stem in the new tripples.

it will work no problem I used the 650 stem with no issues, just be aware of the new ID their stem will create when you account for it with bearings. Basically their stems are just a stretched version of a stock GSXR. I used part number 99-3521-5 (bottom) and 99-3515-5 (upper) bearings from all balls and all went together just fine.


If you're having issues getting the stock stem pressed out of the GSXR triple just give it some heat prior to pressing, Mine was in there pretty tight.

perfect thanks what i needed to know. what are your plans for solving the steer stop issues from left to right? and do you plan to run the 17 up front for a bit, or are you gonna get some laced up 18"-19"? that set up looks great! im a little worried about how much clearance i may or may not have with my 4-1 vance and hines exhaust.

so im curious does the kz650 stem come with that nut on top?

Thanks
eric

I'm currently looking at addressing the stop issue at the moment. Several thoughts since i'm using the stock lower triple, but haven't come to a sure fix yet. I'm probably going to lace and 18 or 19" up front. I'm sitting right around 4 inches of trail so I'm a little worried to bring the overall wheel size down much not knowing what the impact would be. A 4-1 is a little worrying for me too. May have to get creative with a 4-2 (another reason to maintain as close to stock wheel size. Could always tinker with a taller rear wheel to shoot for a little more ground clearance, but then again trail becomes a concern.

I can't remember off the top of my head if it came with a top nut as I ordered the stem, bearings, upper triple all at the same time.