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Front end conversion - was yours worth it ??


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Having read a few posts both here and on the equally brilliant Bikersoracle site in the UK, I thought I'd get some feedback (er, sorry, no pun intended) from those that have changed their front end, be it Firestom (VTR1000), or a complicated USD set up.

If you've made a change, would you be so kind as to tell me what the change was, and how you feel about the results. I'm hoping to be able to do a simple conversion myself, mainly for the brakes as I already have Maxton internals in the std forks. While I appreciate the ultimate way would be a USD set up, form say a fireblade or R1 etc, I'm not sure it's the best bet for me, especially as it would no doubt cost approx £1000 to finish I would imagine. I'm also not sure it looks right cosmetically - something of an overkill, dunno, need to think on that.

My personal preference would be either a Firestorm or CBR600F4i (FX/FY) set of forks, refurbed calipers from that model, and then to get the GP20 fork cartridges from Maxton, to match my Maxton rear Shock, and also 'cause they really know what their doing, and would transform the Firestorm intenals for sure, as I understand they are pretty rubbish as std. I reckon that would set me back about £600 all in, but I could recoup some cash from selling my std VFR forks wth Maxton internals.

One question though - why has no-one done an 800 conversion, especially from a VTEC? I presume because of the differing fork diameters, and the fact that it's just not possible to get the wole yoke tree/wheel interface etc to fit - anyone know more on this?

Any comments gratefull received - pics too of the finished work please if you have them. Thanks.

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Guest btec116

I'm going through a GSXR1000 K7 conversion (see VFR800 track project thread). So not exactly in your scope by the sounds of it... The way I see it there's no limit to what you can stick in there, just find something you like... Seems like alot of people like the F4i front, but wouldn't know myself. I was after a trackable solution, and radial brakes were a requirement to that. Mine has been an ebay project if anything else - how to do a FE swap on a shoestring budget (patience!!!) I think you could go a long way with that budget and maybe have change at the end of it...

But don't get rid of your old forks in a hurry - alot of times (not always) you can keep the internals and fit them to other forks. I'd definitely look into this first, the F4i forks are not that far off it would seem, and Maxton makes some good kit, it'd be a shame to get rid of it if you don't have to.

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On my 02 street Vtec I had Aftershocks re-valve & re-spring my stock forks and have run them Hard for over 50k miles with very good results! Actually they didn't feel that good until I balanced the rear Ohlins with the correct spring, then entire bike was transformed!

Only downside is No adjust-ability

On my 04 Vtec Track bike I installed a full F4i front end w/calipers and radial M/C, new shim stack for stock Rebound valve and changed to large port Showa Compression valves w/new shim stack. Felt Great and fully adjustable.

post-301-0-23654300-1327363714.jpg

post-301-0-71729600-1327363758.jpg

post-301-0-05801400-1327363886.jpg

post-301-0-03821600-1327363933.jpg

W/ F4i forks you can use stock VFR wheel/Rotors or F4 wheel & stock rotors or F4i wheel and rotors. I used a stock 06 Vtec fender on teh F4i forks, only 4 of the 6 mounts bolts work, but that's plenty.

BR

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I just had the internals of my 4th gens reworked. For all of the stuffing around, unless you're going for the look and really need the extra performace, I don't see the point. Yes later USD fork may just perform better than reworked standard forks. I contend that is a MAY perform better.

That said, I do like the look of USDs on VFRs. Not enough to bastardise mine though.

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For the last statement, I really can't see why anyone would put 6th gen forks on the 4th gen. With all the time and effort involved, you might as well do the F4i and have a better upgrade.

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Guest VFRHusband

Did this Suzuki TL1000R Front end on the wife's Gen 3.

DSCN0512.jpg

Is better in the corners than stock the best I can tell. The biggest plus was in the breaking.

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Bellow is my old track bike 4th gen with 6th gen front end, I only used them because I had them from my 6th gen when it was upgraded to USD forks. Due to the LHS fork leg needs the link brake mastercylinder setup there not a good swap, I just filled the master cylinder & sealed it off. Your better off using F4i forks which have the bonus of rebound/compression adjustment. The difference from the standard forks & brakes was worth the change 100 times over & needed it for the track.

post-2353-0-17229900-1327387819.jpg

Bellow is F4i front end I fitted to friends bike, parts were: F4i forks, F4i calipers, F4i master cylinder, F4i guard, 6th gen triple clamps, 6th gen clipons, 6th gen wheel, 6th gen rotors, 6th gen axle.

VFR750 082.jpg

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On my 02 street Vtec I had Aftershocks re-valve & re-spring my stock forks and have run them Hard for over 50k miles with very good results! Actually they didn't feel that good until I balanced the rear Ohlins with the correct spring, then entire bike was transformed!

Only downside is No adjust-ability

On my 04 Vtec Track bike I installed a full F4i front end w/calipers and radial M/C, new shim stack for stock Rebound valve and changed to large port Showa Compression valves w/new shim stack. Felt Great and fully adjustable.

W/ F4i forks you can use stock VFR wheel/Rotors or F4 wheel & stock rotors or F4i wheel and rotors. I used a stock 06 Vtec fender on teh F4i forks, only 4 of the 6 mounts bolts work, but that's plenty.

BR

Bellow is my old track bike 4th gen with 6th gen front end, I only used them because I had them from my 6th gen when it was upgraded to USD forks. Due to the RHS fork leg needs the link brake mastercylinder setup there not a good swap, I just filled the master cylinder & sealed it off. Your better off using F4i forks which have the bonus of rebound/compression adjustment. The difference from the standard forks & brakes was worth the change 100 times over & needed it for the track.

Bellow is F4i front end I fitted to friends bike, parts were: F4i forks, F4i calipers, F4i master cylinder, F4i guard, 6th gen triple clamps, 6th gen clipons, 6th gen wheel, 6th gen rotors, 6th gen axle.

BR / zRoyz,

You both mention being able to use the stock VFR wheel/rotor combo with the F4i forks and zRoys you are using the F4i caliper/master cylinder with that combo. Does that mean that the VFR calipers will not work with the F4i forks? I found a few sets of '02 F4 front ends for sale and thought I might look into this mod, but I would prefer to keep the stock brakes on my '09 w/linked braking intact. (I pressume they need to be F4i, not plain F4?)

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Guest twoeyedbob

I cant really comment.......but i'm going to anyway

I've not really ridden anything much other than my gen 4

Changed the fork oil and kept on top of the calipers

And got a newish shock off ebay

Never ran out of brakes or handling while running with

My mates on new bikes,so why go to the bother.

Maybe if i had something new to compare i'd know what

I was missing.

Had a shot on my friends gsxr 1000 and busa

The only things that really stood out ,was the massive power.

Didnt notice the brakes

Plus the talk of having to upgrade the shock puts me off a bit.

It get's a bit wallowy on really really fast stuff,but im already

In jailbait territory.

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RC51 forks on a 1999 VFR800. No, I would not switch back.

The longer trail due to the RC51 triples different offset makes the bike steer slower (all else being equal) but on my bike, the front end is slightly lower than stock, and the rear end, I raised up, plus the handlebars are wider for more leverage, so it pretty much cancels that effect right out.

The brakes are absolutely stupid, and the ride quality and adjustability are far better than the standard VFR boingers. I added an Ohlins rear shock, courtesy of a VFRd member, and the transformation is complete.

gallery_554_5200_7067862.jpg

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Twoeyedbob - I get your point, and of course it's true that the rider is always key regardless - Ron Haslam could beat me on track even if I had a Fireblade & he had a paddock scooter :smile:. To be honest, I'm as influenced as the next man by all the lovely new shiney toys out there, but there's no way I can afford to replace the VFR with anything significantly better for my budget - I'd have to be looking in the £3500-£4000 range at least. After a bit of casual browsing at all the many & varied "frankenviffer's" on here, I've come to the conclusion that transforming my bike to the way I want it, for my reasons, regardless of future value, will give me more pleasure than trading in for something different. I did in fact try a swap last year - for an Aprila Falco - but you know, on balace, for my life, the VFR is actually a much better bike. Having used the Aprilia brembo's though, it did highlight where I could improve the VFR, and that is the main reason for a front end change, as I already have the benefit of Maxton fork cartridges. It's also a bit of a project thing for it's own sake, within my limited abilities of course.

Thanks everyone for your input. It does seem for me, that the F4i is the way to go, without going too crazy, especially as most things just slot in. Must say that VFRHusband's bike looks well trick - not quite my taste but a credit to you sir !

Re the f4i - does the bike end up with the same geometry - i.e. are the assembled forks the same length as the std 4th gen. I know dropping the std forks by 10mm is a recommended mod, and the Firestorm forks end up 10mm shorter than std, so is the f4i result the same as the Firestorm?

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BR / zRoyz,

You both mention being able to use the stock VFR wheel/rotor combo with the F4i forks and zRoys you are using the F4i caliper/master cylinder with that combo. Does that mean that the VFR calipers will not work with the F4i forks? I found a few sets of '02 F4 front ends for sale and thought I might look into this mod, but I would prefer to keep the stock brakes on my '09 w/linked braking intact. (I pressume they need to be F4i, not plain F4?)

You can't keep the link brakes with F4i forks because the LHS 6th gen caliper mount has the link brake mastercylinder for rear brake & the mount on that fork leg for that system is completely different, you can't really use the 6th gen lower with the F4i because of the compression adjustment adjuster is on the lower F4i fork leg & the reason to upgrade the 6th gen forks with F4i is to gain remote rebound/compression adjustment they have & the 6th gen doesn't. To keep the link brakes & improve the standard forks there are kits aval to add rebound remote adjustment but honestly if you get your 6th gen forks valving & sring rate set up well the only real worth while upgrade is USD forks.

Bellow is my 6th gen with CBR1000RR forks, I have sice installed my Ohlins CBR1000RR forks because the 25mm valving they have suits it better than the 30mm Ohlins cartridge kit in the forks in picture (the forks in picture are now installed on my CBR1000RR as the 30mm cartridges suit that bike better). The difference they make with handling & braking is like drinking your fav beer ice cold to the standard forks drinking it boiling hot.

Frankenviffer MKII CBR

These are Ohlins forks on my CBR that are now on above & above now on CBR, the reason for swap is the 30mm valving is for heavy braking & high front end loading, the VFR doesn't load the front end anywhere near as much as a sportbike.

post-2353-0-36060000-1327413279.jpg

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BR / zRoyz,

You both mention being able to use the stock VFR wheel/rotor combo with the F4i forks and zRoys you are using the F4i caliper/master cylinder with that combo. Does that mean that the VFR calipers will not work with the F4i forks? I found a few sets of '02 F4 front ends for sale and thought I might look into this mod, but I would prefer to keep the stock brakes on my '09 w/linked braking intact. (I pressume they need to be F4i, not plain F4?)

You can't keep the link brakes with F4i forks because the LHS 6th gen caliper mount has the link brake mastercylinder for rear brake & the mount on that fork leg for that system is completely different, you can't really use the 6th gen lower with the F4i because of the compression adjustment adjuster is on the lower F4i fork leg & the reason to upgrade the 6th gen forks with F4i is to gain remote rebound/compression adjustment they have & the 6th gen doesn't. To keep the link brakes & improve the standard forks there are kits aval to add rebound remote adjustment but honestly if you get your 6th gen forks valving & sring rate set up well the only real worth while upgrade is USD forks.

Bellow is my 6th gen with CBR1000RR forks, I have sice installed my Ohlins CBR1000RR forks because the 25mm valving they have suits it better than the 30mm Ohlins cartridge kit in the forks in picture (the forks in picture are now installed on my CBR1000RR as the 30mm cartridges suit that bike better). The difference they make with handling & braking is like drinking your fav beer ice cold to the standard forks drinking it boiling hot.

These are Ohlins forks on my CBR that are now on above & above now on CBR, the reason for swap is the 30mm valving is for heavy braking & high front end loading, the VFR doesn't load the front end anywhere near as much as a sportbike.

That's what I figured. I didn't want to get too carried away but I would like a little adjustability on the suspension. Since my bike does dual purpose, commuter and partime playbike, I want to be able to tune the suspension to what type of riding I'll be doing. However, since its primary role is to get me "there and back", I don't feel I need to go too hog wild. If I realy feel the need to go knee dragging or hit the track, I usually take the Duc. As far as the after market "remote rebound/compression adjustment" kits, those might be more of what I'm looking for.

Cheers.

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Guest daemontrym

Jaime Daughtery built a custom 929 shock for me and made custom shim stacks for me, I run them with 15wt oil and hyperpro springs right now. I reverted back to this setup from 1.0KG springs and honda 5wt because the front end feels much more positive especially 2 up. I was happy with the original suspension before I threw a passenger in the mix. Plus being deployed at the time I fell in love with my 4th gen and figured I would not better it with a newer bike. (came from 07 R6)

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Guest twoeyedbob

I already love everything about my gen 4

I'd be worried about changing anything in case

It turned into one of those things that's never quite right

A bit more this/that and it'll be right

It's all well balanced at the moment,

Of course that might mean it's soggy at both ends

But i know every nut and bolt and all it's boingy bits.

But even if i spent a fortune i'd still be 50-80bhp

Down on the latest thing

I just love that every season it get's more attention

Down the local bike meet,and that's before they see 90'000 miles

On the speedo

I love chasin and passin the shiny brand new sportsbikes on my favourite

Twisty road.

Sorry ..turned into a homage to ....still ..the best bike ever

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I tossed a set of vtr (firestorm/Shawk) forks in my 96 4th gen. They have been massaged by my suspension guy, and are running rc51 brakes (straight bolt on). That and a penske out back make it great for everything including track days.

The Shawk forks are cheap, use the stock triple, and with the vtr axle and spacers uses the stock front wheel. I can't see more bang for the buck.

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I see Roy's (zRoyZ) chimed in, so here's where the first USD coversion he did on his VTEC ended up when he sold the bike:

post-1160-0-28685000-1327453551.jpg

Here's the spec sheet for the original VFR1 http://www.vfrdiscus...pic/38679-vfr1/

Pretty much the whole thing went in as is, though there was some fiddling with moving oil cooler, shaving the inner fairing, moving cables, pipes etc

Is it worth it? Let's face it any improvement on the stock suspension and brakes has to be worth every cent - both are critical in keeping you out of trouble and as anyone with any sense will tell you, the only two things the last and best 750s need are decent brakes and suspension. The F4i swap - adjustable suspension, much better brakes - is one of the easier and cheaper options, uses Honda parts (so no faffing about with different axle specs, disc spacing, wheels, wheel bearing sizes) and will make a helluva difference.

Is it worth spending so much on a USD set up on a bike this old? In my view the question answers itself - the people who do this sort of thing aren't about to sell their bike so resale figures are irrelevant. In the end it comes down to turning a great bike into a fantastic one. As I said to Roy when I first rode mine with the R1 front, it feels like I've suddenly got 2-3 seconds extra per corner - the $$$ spent automatically justifies itself. The brakes are brilliant, but the irony is that cos the handling is so good I use them less than I did on the OEM set up. It steers much quicker yet is utterly stable (no hands-off headshakes at any speed) and it doesn't chew front tyres anywhere near as much. It will keep up with any modern sports bike in the twisties - or would if I wasn't such a pi$$-poor rider.

And it looks mint :tour:

Edited by Parker
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I am very happy with my VTR forks and '99 CBR900RR (same as RC51/F4i/CBR929) brakes. I did the fork valving myself without any prior experience and got lucky as they feel very good. Couldn't you use the Maxton internals in the VTR forks? I think they would switch over very easily.

Edited by FinnRC36
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As the OP originally ask what people think of their front end conversions & I’m probably the only one on the site that has ridden on the most VFR’s with conversions I thought I would try my best to explain differences. When this type of question is asked you read a lot of posts from those that state “I don’t ride hard & my standard front end works great” which unfortunately without wanting to upset anyone who feels that way is like a person living in a box & thinks it’s great because they have never lived anywhere else.

Suspension for motorbikes evolves just like everything else & there is the other fact motorbikes are built for a target market to a price point by manufactures so you simply won’t always get great suspension standard with every bike, what you get is adequate suspension. The main purpose of suspension is to keep the tyre firmly planted on the road surface at all times nothing more, but to do so with so many variables is no easy task. Let’s take for example a high end shock the Ohlins TTX which is cutting edge, but since its release Ohlins have changed the internal design for the masses many times. That doesn’t even account for an individual having there suspension tuner do more modifications. The standard VFR suspension say for example the 6th gen has been the same design from factory from 2002-2012> the Ohlins TTX shock hasn't even been out that period & has had many internal revamps.

My 6th gen to use as an example front end has had standard forks re valved, RC51 forks, R1 05 forks, CBR1000RR forks with 30mm Ohlins cartridges & now Ohlins FGRT forks with 25mm cartridges. All the fork swaps have had extensive re valving to dial in my preferred feel option. Each fork has worked the way I have wanted them for my preferred feel, but the main difference with all these upgrades has been safety. The difference between the R1 05 forks & the CBR/Ohlins forks is next to nothing & I would still have the R1 forks installed if I hadn’t have sold the bike & then bought it back 2 years later. But to put that into prospective the R1 forks had valving specially designed for me & the VFR setup, none of the valving inside forks was standard R1.

The difference is like so, the standard forks have zero remote adjustment rebound/compression so the internal valving has to deal with so many variables you are making compromises by design. They also flex more than USD forks which isn’t major but the effect is noticed the most under hard braking. What is bad about the flex is the heat & wear it causes to internal parts, the more heat & wear the quicker your fork oil is contaminated. Contaminated oil slows response which is what suspension is all about, remember the standard forks have no rebound/compression remote adjustment so you can’t even compensate as the oil starts to get contaminated. This scenario is at its worst with 4th & 5th gens because there forks flex allot more having smaller diameter fork tubes & I have seen so many of these fork internals that bypass oil in a major way past the cartridge shaft seal due to wear from the flex. If your shaft seal leaks oil flow doesn’t flow through valving it squirts out the seal, outcome poor response.

RC51 forks are great forks compared to the standard forks but there an old design & there is a trade off with rebound/compression with them. You can’t valve them to get both compression/rebound very close to perfect, the suspension tech will make a compromise between the 2 when valving. You can notice this effect yourself (well I did) one click more compression makes too much difference & until you find a happy medium you’re always going one click up or one click down. The reason this happens is the VFR doesn’t load the front end much at all so you set compression soft to help load the front yet you hit a big bump & there is too much fork travel. The brakes aren’t really any better than the standard VFR brakes as far as callipers & clamping force, the big improvement is fork compression valving. This with the higher rigidity of USD forks (less flex) is what improves braking over the standard forks.

R1 forks are cutting edge for their price point & from 04 till 08 haven’t changed that much internally, there very easy to setup for the VFR & there remote rebound/compression adjustments are very precise. The major effect I notice changing to these forks was being able to change direction close to full lean angle mid corner without the bike becoming unsettled at all. That is a major safety improvement if there is a rock etc you didn’t see mid corner. The feel I obtain with these forks I couldn't with standard is the front end bobing up & down as it goes over bumps, but it's only the fork movement I'm feeling the front end stays more or less at the same height, the wheel is following the road surface sending great feed back through the bars. The other added advantage was the radial brakes which can be used to their full because the R1 forks compression is so good & the same rigidity as the RC51 forks.

CBR1000RR forks are more or less the same as the R1 but I can only comment on the Ohlins cartridge aspect because I haven’t ridden a VFR with modified standard valving. As mentioned the direction Ohlins has gone with really only 30mm valving available now is sportbike tech which place extreme loads on the front end, which the VFR doesn’t. This type of valving design is high stability under brakes, unfortunately I found due to the VFR not loading the front end like a sportbike I couldn’t gain the feel I prefer form them & my suspension tech did try a number of modifications to try to attain the feel I like. The front end mid corner due to unloading to quickly felt flighty & didn’t matter what rebound remote adjustment I tried on the fly I just didn’t like that valving on the VFR. On my CBR1000RR is another storey there outstanding.

The Ohlins (CBR1000RR) FGRT forks I have come with 25mm cartridges (the newer model now has 30mm) & these suit the VFR much better & I now feel there as good if not better than my old R1 setup.

The bottom line is response time as you need your forks to keep that contact patch at all times which is a major ask with all the variable road conditions. Remote adjustment rebound/compression on the fly with forks that are more ridged so less heat & wear internal components is everything when the flow rate of fork oil is what creates the response you need to keep that front wheel planted at all times. Just think how your standard forks feel straight after an oil change & then think about keeping that oil in that condition for a longer period & having adjustment to prolong the response as the oil starts to contaminate. Since installing the first USD upgrade (RC51) I haven't had a front end slide, not once, yet with standard forks even with valving & correct springs addressed I had many a slide, that is not in gravel or very lose surface as no tyre can grip if what it's griping to moves. Just for the record my riding style is fast into a corner less throttle out due to lean angle so I need to trust the front end, it's not always the fastest way around a corner but it's what I enjoy the most.

Hope I haven’t bored anybody with my speel.

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zRoyZ - Many thanks for that thoroughly informative post - I should have known, but I think I'm going to have to think about this front end rebuild project a lot more before I commit to anything, and re-read all your posts about the conversions you've done. The R1 set up on Parkers 750 looks great, apart form the master cylinder, but I guess there's limited choice for something to match the std clutch cylinder.

You clearly know your stuff, and it's amazing I get to benefit from your knowledge - so thanks again. Lovely looking VTEC you have there, a thoroughly sorted motorcycle.

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