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5th Gen VTR1000 fork swap


Guest cdmpc

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Guest cdmpc

I have installed a straight set of 98 VTR1000 forks in my 98 VFR.

I am using stock VFR rotors. I have a set of VTR 1000 calipers I am using also; but while the bolt holes do line up they are about an 1/8 inch away from the caliper mounting holes. The axle spacer for the right leg is in place as well as the left side "ring".

Any input would be greatly appreciated! I understoood from my research that there was not offset issue using this setup and that it was a drop in swap. So, I presume I am missing something. Although, I have the resources to fabricate anything that is needed.

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So, when you measure your forks assembly bolted together with the triples and calipers and you measure your front wheel with the brake rotors mounted, what is your distance from center of rotor to center of rotor and your distance from center of caliper to center of caliper?

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Do you have the VTR set? May need them to make it work?

Negatory Ghost Rider....fleabay buy.

I am thinking the spacers are probably the issue; or at least I know it can be fixed with spacers. As CornerCarver pointed out; some measurements are in order.

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I have installed a straight set of 98 VTR1000 forks in my 98 VFR.

I am using stock VFR rotors. I have a set of VTR 1000 calipers I am using also; but while the bolt holes do line up they are about an 1/8 inch away from the caliper mounting holes. The axle spacer for the right leg is in place as well as the left side "ring".

Any input would be greatly appreciated! I understoood from my research that there was not offset issue using this setup and that it was a drop in swap. So, I presume I am missing something. Although, I have the resources to fabricate anything that is needed.

I am using VTR lowers on VFR800 upper tubes. Also using RC51 (SP2) calipers with the stock 5th gen wheel and rotors. I have also noticed a bit of mismatch of caliper alignment. That the inner pistons were closer to the rotor (if inner and outer pistons are in same relative position to the caliper face) than the outer. I had considered going anal and grinding custom washers to put between the fork mount and caliper, but for the moment I am just using a standard off the shelf washer to help make-up the difference. I may still go for getting the measurements and getting an exact washer thickness to use, but that is not at the top of my "to do" list. I hadnt given it a high priority since overall its just positioning where the pistons and pads clamp together in total.

(From comments - Maybe its looking like that perfect thickness spacer washers are a good idea?)

KPerham - I also have a bit of the "vibs" on hard braking and not totally happy with it. I have cranked up rebound damping some and that helped. I thought I could attribute part of the cause to the system has less than optimum stiffness, but now I see you are having a simular issue with the RC51 forks that are mucho stiff. - Btw, I am using stock SP2 pads.

-I'm still head scratching a bit on this. Gotta admitt, for the moment at least for the front end, I'm in a "just ride it" mode, as its not bad enuff to mess with. I'll probably attack it at some point, but I want to work out the electrical garbage first.

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I'll try not to jack this thread to my braking issues... Lol!

I take it by Mello's reply that the VTR calipers are solid mount opposed piston type. So that theory is out. Probably spacers. At one point I was going to try F4i forks and brakes with VTec triples and my '99 wheel. Baileyrock advised that I'd likely need F4i axle and spacers for that setup. Or maybe VTec. Don't remember. Not 5th Gen at any rate.

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okay guys let me do some tinkering tonight and I will advise. Reality is washers will be the short term and custom machined spacer will be the end game. In my mind not worth tracking down more Superchicken parts...

Next topic is the front master cylinder....I dont remember which guru pointed out the danger of using the VFR mc but I am going to do a driveway/neighborhood run to test my Nicky Haden catlike finesse soon.... ;-)

I do have a VTR mc- but cant help but wonder how sensitive the vfr mc is. So, I will break out my Icon carbon flip-plops and Dianese wife beater for safety sake....

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Don't use the VFR master.

thats pretty definitive there Perham.lol

Yeah...

VTR calipers are 4 piston each, probably 30/32mm or 32/34mm

VFR master only operates a total of 4 pistons, 2 per caliper. Much smaller pistons (20mm? Really no idea), as each caliper actually houses 3 pistons.

If the VTR calipers are 30/32, the master is likely marked with 3/4. As in 3/4 inch bore. Basically equal to 19mm.

If it's marked 11/16 then it's 17mm.

I think the VFR is 1/2? So somewhere in the 12-13mm range.

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Don't use the VFR master.

thats pretty definitive there Perham.lol

Yeah...

VTR calipers are 4 piston each, probably 30/32mm or 32/34mm

VFR master only operates a total of 4 pistons, 2 per caliper. Much smaller pistons (20mm? Really no idea), as each caliper actually houses 3 pistons.

If the VTR calipers are 30/32, the master is likely marked with 3/4. As in 3/4 inch bore. Basically equal to 19mm.

If it's marked 11/16 then it's 17mm.

I think the VFR is 1/2? So somewhere in the 12-13mm range.

I will check back in after I find the caliper bolts....dang it. It is a project afterall!!! Thanks for the feedback~

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Shoot! Minor screw up on my part, but the basic theory is the same. Bigger caliper pistons require a bigger bore master. So the 32/34 has a 19mm master and 30/32 has the 17mm. Either way half inch won't cut it!

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Some fairly good guesses in this thread--but...

The 5th-gen VFR's fork spacing is 204mm; the VTR's fork spacing is 192mm. (This is determined by the triple clamps.)

The brake disk offset is 17mm for both bikes, and caliper mounting lugs are generally in the same relative places on the fork lowers, so the only way this combination could fit on a drop-in basis is if the VFR's wheel hub (where the disks mount) were 12mm wider than the VTR's. Unfortunately, it is only about 7mm wider...which leaves you with 2.5mm per side to make up with caliper spacers. Does that ring a bell?

The axles and spacers should also be carefully measured, as the VFR's axle length and spacers may no longer be appropriate.

The VTR1000F master cylinder is actually 14mm, and the VFR master is actually 12.7mm (marked "1/2"). Using the VFR master with the VTR calipers would give you more leverage (i.e., "power") at the expense of "feel" and (more importantly, to my mind) increased lever travel. The latter means that whilst you're busy locking up your front wheel, your brake lever might come back to the bar..neither of which are particularly helpful unless you're suicidal. Most 14mm m/cs are remote-reservoir types, and you can find them on everything from Fireblades to, well, Fireblades (and VTRs). They are helpfully marked "14" on the casting. However, there are not a whole lot of integral reservior-type m/cs in 14mm, if you're going for the OEM VFR look. I have one on my FP (with VTR fork conversion) and I think it was sourced from an ST1100. HTH.

FYI, VTR caliper pistons are actually 30/27 (four of each), and the VFR's four front brake-activated caliper pistons are actually 27, 25.4, 25.4 and 22.65 (go figure).

Most Honda master cylinders are 1/2" or 14mm, with a relative few being larger sizes, such as 5/8", 11/16" and 3/4" (though I haven't really kept track of the radials).

1/2=12.7mm

14=14.0mm

5/8=16.0mm

11/16=17.5mm

3/4=19.1mm

(NOTE: ALL MEASUREMENTS PROVIDED HEREIN ARE APPROXIMATE--PLEASE MEASURE FOR YOURSELF!)

Ciao,

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  • 2 months later...

dont want to thread jack but,

Ive just done the vtr forkswap as well, with vtr 1000f calipers and master cylinder, Ive spaced the calipers with washers as descibed in the above posts, Im posting here cos I ve noticed vibration under braking too,

I thought it would clear as the pads bedded in, (new oem pads, old vfr discs) but if anything its getting more noticable, its not the end of the world but its a little disconcerting and i see posters above saying similar things.....

other than that im delighted with the conversion.

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  • 1 year later...
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Im posting here cos I've noticed vibration under braking too,

Check your head bearings. I had the same on my delinked VFR & adjusted the bearings & its gone away :)

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  • 3 weeks later...

Im posting here cos I've noticed vibration under braking too,

Check your head bearings. I had the same on my delinked VFR & adjusted the bearings & its gone away :)

in the end my issue was a dodgy thread on one of my calipers, but i was so giddy to ride i just lumped some thread lock in an went for it, (sounds stupid with hindsight i know) anyway, saw the error of my ways got the caliper sorted at my local machine shop..problem solved, havent had an issue since , and would definitely recommend the conversion to anyone considering it.....

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Off topic note - I had a few people ask for my adaptor brackets to mount the 5th gen fender on the VTR fork legs. Made a batch and have a few left over sets. Check classified or PM. :cool:

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  • 9 months later...

Hi guys. I've recently bent my forks and as my calibers needed refurbushing(and I don't like the linked brakes), I tought of delinking the brakes and changing the front braking system and forks. I'm thinking of buying the whole front braking system (M/C calipers, brake lines) and forks from a 1998 VTR. I'm thinking of using my 99 VFR triple, wheel and discs. Basicly it has to fit without any modifications except the alignment of the discs and calipers, right? And which axle and spacers did you use VFR or VTR(with the VFR wheel)? Thanks in advance! :beer:

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Hi guys. I've recently bent my forks and as my calibers needed refurbushing(and I don't like the linked brakes), I tought of delinking the brakes and changing the front braking system and forks. I'm thinking of buying the whole front braking system (M/C calipers, brake lines) and forks from a 1998 VTR. I'm thinking of using my 99 VFR triple, wheel and discs. Basicly it has to fit without any modifications except the alignment of the discs and calipers, right? And which axle and spacers did you use VFR or VTR(with the VFR wheel)? Thanks in advance! :beer:

Dude - its pretty much a drop in. --- I did nears exactly the same thing, except I used the stock VFR800 upper tubes, which were a few mm taller and then RC51 calipers and mc.

Some stuff....

- Chances are you will need different brake lines.

- Stock wheel, rotor, spacers, axle work fine.

- The VTR fender wont bolt on because the triple tree stance is wider.

- I designed adaptor brackets that make bolting up the stock 5th gen fender to the VTR forks easy. (I have a set left

for sale.)

- Oh yeah, the rear you will need to change the master cylinder to a 14mm - VTR, RC51, F4i and I'm sure others use one like it. Also bridge the rear pistons together. -- Some guys just use both brake lines, personal taste I guess.

Check my gallery for the bike build and feel free to PM me with questions.

--------------------------

May as well add... there are umteem options to change forks, but another "quick" option is F4i forks and 6th gen triples and clip ons.

Others -------- Plus the gamut of other USD Frankenviffer changes here..... :cool:

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What MD said, you must use the axle and spacers from the triple clamps that you select as this sets the spacing between the fork bottoms where the axle fits...

If you source a VTR set of triples you could use the VTR fender/mud guard but part of the reason guys upgrade the VTRs with fork braces is due to the triple clamp spacing so best to stick with VFR triples and fab or source some mounting brackets to adapt the fender of your choice.

With RC51 front master/calipers this upgrade is outstanding!

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If you source a VTR set of triples you could use the VTR fender/mud guard but part of the reason guys upgrade the VTRs with fork braces is due to the triple clamp spacing so best to stick with VFR triples and fab or source some mounting brackets to adapt the fender of your choice.

Yeah, I wasnt clear - VTR triples are narrower in stance than the 5th gen triples, so the SH fender wont fit. The 5th gen fits only with some kind of adaptor bracket.

Here's a pic of the CNC design that I used.

Mountonforks10.jpg

With RC51 front master/calipers this upgrade is outstanding!

Totally agree with that! :beer:

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  • 2 weeks later...
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Just to be clear. With the VTR triples, it is a straight swap? Taking into account that the master is is also VTR. Nothing VFR is left behind on the front.

Thanks in advance. Looking at front end tomorrow.

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