19" front wheel/tyre

[modnrod]

OK, I know most prefer the 17" front for a much greater range of tyres, especially radials. But personally, I prefer the cruiser/muscle bike look, and having bumpy roads also prefer the ride quality of the taller tyre.
110/90x18 is 654mm, 120/70R17 is 599mm, so 2" shorter.
I started looking at 19" front rims that might work, tyre range is much better than the 18" front tyres, and some radials are also available (Michelin, Metzeler, Avon), but also the 100/90x19 is the same height as standard.

I came up with the front rim off the early '80s Yamaha XV1000. It has 5 thin curved twin-spokes around the wheel, and the XV1000 weighs in at 235kg stock, so close. Rim size is 19"x1.85", and the hub where the brake rotor bolts onto is a very common size of 64mm ID and 80mm 6-bolt PCD. There are brake rotors for this size from 270mm all the way to 320mm. I have also calculated the weight of the XV wheel with tyre, twin rotors, etc, to come in at under 10.5kg..........or 3kg less than stock Vmax front, which is AN AWFUL LOT (smae as a 17" off GSXR/ZX/R1).

To make it a bolt-up operation, you need a bearing that fits the 42mm OD of the wheel hub, to the 17mm axle of the early Vmax (mine is a 1987). You will need bearings 6004-2RS (C3 hi-speed of course) x2, seal 45x56x7, seal 17x42x7, and a spacer made for the inside of the wheel that is 20mm OD x 17mm ID (bearings have a 20mm ID). All standard speedo drive stuff on the early Vmax's will fall into place, they use the same drive unit.

My bike is getting a 320mm floating disc rotor and a Nissin 4-pot caliper off a 2008 GSXR, one side only, and to drive it correctly I'm using a 14mm brake M/C off a Yammie XJR1300, but on one side only..........I want all the Harley guys to see my lovely shiny whitewall tyre as I suck their mirrors off with a REAL cruiser! :clapping:If I need more brakes I can do the other side too.

Hope it helps someone with similar aims.

 

[[email protected]]

Great info!
I like the look of the 19" fronts.

 

[sdt354]

I'd love to see a pic if possible. Thanks for posting the idea.
Steve

 

[sdt354]

I never regretted the Nissin 4 pot adaption. Though I have 2. They work great even with the 280 mm rotors and stock master.
I'm having a little math issue with tire sizes. Seems you don't. iF i PM you my calculations will you verify for me?
Thanks,
Steve-o

 

[Rollie]

Are you using brakes on one side only for looks ? Weight savings ? You only need a one time panic braking situation to remember why they came with both side braking. Just saying.

 

[[email protected]]

I never regretted the Nissin 4 pot adaption. Though I have 2. They work great even with the 280 mm rotors and stock master.
I'm having a little math issue with tire sizes. Seems you don't. iF i PM you my calculations will you verify for me?
Thanks,
Steve-o

Try this for tire diameter calcs

http://www.rbracing-rsr.com/tirediamcalc.html
or
http://www.1010tires.com/tiresizecalculator.asp
for comparing, I like this one
http://www.csgnetwork.com/tireinfo4calc.html

 

[one2dmax]

We have sold 19" front RC Comp Wheels before and they look great on there. Help fill up the wheel/tire gap on the fenders and get matching tires if doing an 18" rear 19" front (same setup as the Vrod has).

The single rotor works well and we;ve also done a 320mm single six piston conversion which gives more surface area for both the pad for traction and surface area for the pistons for better feel. It brakes as well or better then the stock later model 4 piston brakes with dual rotors.

We did it for looks as well as reciprocating mass reduction. Just because there is one rotor doesn't make the bike pull to one side when you put the brakes on. And the larger rotor has a far greater leverage then the smaller rotor so you can get by with just one. Of course 2 would be even far better!

Sean

 

[bazwell]

I like your work modnrod. Sounds like you have found a winning combination! Pics please when it's done!

 

[Fire-medic]

OK, I know most prefer the 17" front for a much greater range of tyres, especially radials. But personally, I prefer the cruiser/muscle bike look, and having bumpy roads also prefer the ride quality of the taller tyre.
110/90x18 is 654mm, 120/70R17 is 599mm, so 2" shorter.
I started looking at 19" front rims that might work, tyre range is much better than the 18" front tyres, and some radials are also available (Michelin, Metzeler, Avon), but also the 100/90x19 is the same height as standard.

I came up with the front rim off the early '80s Yamaha XV1000. It has 5 thin curved twin-spokes around the wheel, and the XV1000 weighs in at 235kg stock, so close. Rim size is 19"x1.85", and the hub where the brake rotor bolts onto is a very common size of 64mm ID and 80mm 6-bolt PCD. There are brake rotors for this size from 270mm all the way to 320mm. I have also calculated the weight of the XV wheel with tyre, twin rotors, etc, to come in at under 10.5kg..........or 3kg less than stock Vmax front, which is AN AWFUL LOT (smae as a 17" off GSXR/ZX/R1).

To make it a bolt-up operation, you need a bearing that fits the 42mm OD of the wheel hub, to the 17mm axle of the early Vmax (mine is a 1987). You will need bearings 6004-2RS (C3 hi-speed of course) x2, seal 45x56x7, seal 17x42x7, and a spacer made for the inside of the wheel that is 20mm OD x 17mm ID (bearings have a 20mm ID). All standard speedo drive stuff on the early Vmax's will fall into place, they use the same drive unit.

My bike is getting a 320mm floating disc rotor and a Nissin 4-pot caliper off a 2008 GSXR, one side only, and to drive it correctly I'm using a 14mm brake M/C off a Yammie XJR1300, but on one side only..........I want all the Harley guys to see my lovely shiny whitewall tyre as I suck their mirrors off with a REAL cruiser! :clapping:If I need more brakes I can do the other side too.

Hope it helps someone with similar aims.

Hey, I have one of those wheels sitting in my shed! I almost took it to the scrap metal dealer! The narrow tire/wheel should help sharpen the steering too.

 

[modnrod]

The main reason for me is the weight saving and tyre choices the 19" opens up, and I went for an early Yamaha hoping the speedo drive would have similar ratios.........to end up with a drop-in speedo drive was a bonus! Other wheels which apparently fit are XS750 and XJ650, but not sure.

At the moment when Sean's oil pump kit gets here (thanks for that man, much appreciated), I'm just trying desperately to get it ready for the track in a couple of months, in between new babies and finding somewhere in my little cottage to stash them!

So far I've pulled out 30kg in street spec, with still standard look and parts........did you know the little steel undertray for the back fender (holds taillight and plate) weighs in at nearly 3kg? Holy crap!?!?! HA! HA! The weight should be good for a few tenths easy, but in all the time I've had the bike I've never had a clear run down the 1/4, either no V-boost, jumping in 2nd, etc. No idea what times to expect, but I only need an 11 to qualify, so should be OK.

It won't be mounted for a while yet, but I'll send photo's when done. 3kg off the unsprung weight on the nose will help turning/steering no end.

 

[modnrod]

OK, PIctures!
The first shows just how completely unready the bike is for anything, let alone a track meet! HA!HA! It's only a day to put it all back though.
The 2nd shows a pic of the XV wheel overlaying the standard front, for an idea of size.
The 3rd shows the XV wheel on it's own. I will polish the rim up, then paint the centre black with polished spoke centres, anyway that's the plan at the moment.

 

[bazwell]

That wheel is quite good looking!

 

[one2dmax]

I'm not a particular fan of the curved wheels but maybe once chromed up they will look good. You may have to make a rotor carrier to get the larger rotors and correct offset so they fit in the forks correctly.

Sean

 

[modnrod]

The rotor offset I've chosen is 10mm Sean (I can pick from flat up to 22mm). After some measuring, the rotor I've chosen, together with flat 8mm plate for the caliper adaptors, will centre the caliper over the disc perfectly, and allow 5mm clearance for the caliper to wheel spokes.. I'm getting the rotor from Metalgear, an Aust company coz I have a pdf file off all their rotors from 270 to 320mm (used to do parts in a dealership for a while), but I can find out what the disc comes off if you like.

I like the spokes look, it reminds me of the light mag racing rims of the early '80s, but it is a personal thing as I said. Each to their own. unk:

 

[Fire-medic]

Just wondering if any of you Antipodeans have seen this fellow's 19" front wheel, or if he's been able to break-away from baby duties to do any more work on this or has any pictures to share?

 

[FootNote]

I have seen another bike with the larger front wheel and love it. Just sucks that wheels are just about the most expensive upgrade outside of boring out your motor.

 

[Fire-medic]

Anyone heard anything else on this? Just wondering. As mentioned in the thread I have the same front wheel collecting dust. Would be interested to find out about the rotor application he was going to do, what bike uses it (for parts-sourcing), & the spacer dimensions for either the inside wheel spacer between the races or the disc rotor spacer.

I have a 110/80-18" Bridgestone BT-023 ordered along w/a same in 160/60-17" radial for the rear. I got a super deal for the pair, <$200/pair, mounted/balanced. The rear wheel is from another member thru Kyle (Kosman 5.5 X 17") & went w/a bit narrower rear tire to see if it helps speed handling transitions side to side.

It would be fun to throw-on a 19" wheel to mix things up. I have some front end improvements to install too. Already did a late-model front end on my '92 & FZR1000 calipers, All-Balls steering head bearings, silver metallic powder coated triple trees & etc. Ricors & Race-Tech springs are waiting to be installed.

So any news about the 19" fitment?

 

[MaxMidnight]

The narrow tire/wheel should help sharpen the steering too.

...but the larger diameter wheel and tyre combo may have a larger moment of inertia (resistance to change of direction) due to the gyroscopic effect which would require more force to make a turn?

 

[Fire-medic]

W/o any way other than trial & error to measure it, I would assume that a significantly-narrower 19" wheel will exhibit less rotating mass effect by comparison w/a tire/wheel combo weighing significantly more. An easy way to test my hypothesis would be to take a 700C bicycle wheel/tire in say a 19 or 23 mm size, hold the axle in your outstretched arms, and spin the wheel. Now tilt the wheel left & right. Then do the same thing w/a 26" x 2" wheel/tire for an off road bicycle. The lighter, narrower, taller 700C will easily display less resistance to transitioning from left to right. Same principle on a VMax? I am not sure what the 19" wheel measures in width vs. the stock 18" w/o using the tape, think it's 1.85". If you want to run radials, I dunno if the 1.85" width is sufficient to allow the tire to take its designed profile, and that is a question.