New Brakes + Winter upgrades part two !

Well having spent last summer running around on my delinked brakes, it was obvious that the only area that the bike was lacking was in front end braking. The delinked & circuit integrated front calipers with CBR600F4 master cylinder were just NOT up to the job of stopping the bike as well as I would have wanted.

A track day on a CBR600RR showed how poor the brakes were by comparison, so something needed to be done. I had previously come across Mellow Dudes VFR delinking saga & liked the idea as a simple means to upgrade the front forks to NISSIN 4 pot calipers. This involved sourcing some VTR1000 front fork lowers & a set of Nissin 4 pot calipers, the CBR600F4/RC51/SP-1/CBR929/954 calipers are all worthy candidates.

I used to own a CBR600F4 & having already got the master cylinder for my modified frontend, then a set of those calipers would have been ideal, but I got a good deal on a set of CBR929 calipers (34/30mm pistons). The 600’s are 34/32 & give a 35/1 ratio, the 929’s give 32/1 ratio which is still very good for feel. So I went with those & refurbed them with a complete Titanium fitting kit. These calipers & fittings saved 1Kg over the VFR’s modified units I was running.

I sourced a set of forks & stripped off the lowers, then cleaned them & filed off any external mould flashing & removed enough metal from the lower bolt mount to clear the new calipers. I then sent them to be bead/vapour blasted & then had them anodized. The anodizing turned them from shiny bright alloy to a dull grey like a primer colour, so the outsides were primed, painted & lacquered, rather than just the lacquer I was expecting to do.

Next, I stripped the forks out & removed the VFR inner chrome stanchions along with the Traxxion-Dynamics AK-20 cartridges & transplanted them into the new VTR lowers. The VTR fork lowers share the same axle sizes as the VFR, so everything just bolted back up. I then discovered a problem. The forks seemed to have about 3mm of free play up/down the inner stanchions at full extension, with no apparent spring force. They were not like this in the VFR lowers beforehand & all spacers had been used in the rebuild. So I stripped them out & took the innards out of one of them. The top out & compression springs plus all associated spacers were in there as per specification!!??



The VTR & VFR lowers share identical outer length dimensions & using a tape measure appear to have the same internal dimensions as far as length is concerned, so I couldn’t see where the problem lay. I asked some experts, Traxxion & Reactive Suspension (who fitted the cartridges) & a local bike shop mechanic & they had not come across a similar issue so had no answer for me. I’ve stripped cleaned & reassembled plenty of forks in the past & never had an issue, so all I could think of is there must be some difference in the lowers!

So playing with the assembled leg, if I wound the preload up to max, then the free play was almost eliminated & you could just feel the start of the springs acting in either direction. So I reassembled the other leg & played with additional base preload settings & ended up adding an additional 10mm spacer which when fully assembled completely removed the play & the lower was then always under spring control. I did the same to the other leg & hey presto when fitted back in the bike, the problem was gone & the static sag was perfect.

So I added the new brake calipers & the disc’s are in a different position relative to those on the VTR, so the calipers require spacing away from their mounting points to get the disc central in the calliper. I used 2 x 1.5mm alloy washers per bolt to achieve this. Once I was happy that the discs were central in the callipers, I cleaned the callipers mounting faces & the washers & superglue'd them together, so when I drop the calliper I don’t have loose washers flying around!





The next issue which I knew from MD’s (Mellow Dudes) experience I was going to run into involved the front mudguard/fender mounting. The VTR forks whilst similar to the VFR’s, are not mounted in the same yokes/triple tees. The distance between the fork legs is much narrower on the VTR, so the VTR fender will NOT fit once the legs are mounted in the VFR yokes. The VFR fender will not fit as the mounting points on the VTR lowers are in the wrong place! How to resolve this?
Well by chance MD had contacted me to ask if I was interested in his fender adaptors as I had contacted him previously about the front fork conversion & he had had some other people enquire about the adaptors & needed some orders to get the price down to a useful break point to make it worth getting some made. So I ordered a set. They are very well made & he was able to have them made & delivered before I had actually finished the conversion.







When they turned up, even though they were alloy & very well made, they seemed rather heavy to me. Having spent good money having a Titanium axle & a few other parts made, I was not going to add 92grams per adaptor to my forks. I have managed to knock 3.75Kg out of the frontends unsprung weight, so decided to see if I could modify these to make them lighter. The pictures tell the story from 92 down to 31grams & as they are invisible with the fender in place I was not too concerned about getting them looking nice. They are strong enough to do the job & mounted on M6 cap head alloy bolts, the steel ones in the pics are just for test fitting.









The bike is not yet fully back together as I’m working on a few little bits as detailed below. The front brake feels much better & the pads aren’t even bedded in yet, when they are they should be good enough for my needs.





The other things I’m just finishing are adding a Voltmeter, after the RR crapped out last year, I’d like to keep an eye on this. No pics yet.
I’ve mounted a combined air horn unit below the starter motor, as the standard horn is very feeble. It’s a mod I’ve done to all my bikes since I was a courier, as blind drivers crap themselves when they think a 40footer is about to wipe them out. So much better than me being wiped out. When I sold my CBR600, the shop owner took it for a test ride & nearly crashed when he tested the horn by tooting at a friend on the street, I’d forgot to mention the air horns & he hadn’t noticed them, so thought he was being run over !



I’m adding a quick shifter button that works by cutting fuel to the engine momentarily via the PC3 quick shifter function.



I've also removed the O2 sensors & put bungs in the exhaust holes & removed the sidestand switch.

Last but not least I’m adding a gear indicator. I bought a cheap one from Hong Kong, that uses a magnet & a couple of reed switch sensors, so no need to tap into the bikes wiring harness & it will even display neutral if you tap into the neutral switch output. Still in progress will start a thread when I’ve got some pics.


Then it’s fairing on & enjoy the summer

 

Cool. That is a nice upgrade. I want to do the same on my VFR and the suspension too..

 

All I can say is "FAR FUCKING OUT MATE!!!"

Great write up, Great Pictures...

btw - I always hated linked brakes...I have an F3 front wheel on my 91 that was a direct bolt on. Re-building my front calipers was one satisfying braking experience, along with the re-built front master cylinder. Always run-stainless lines.

Can you tell me what make/model air horn you installed ???

 

Not sure what make/model it is as i tossed the box once I worked out it worked & modded it to fit where I wanted it. Listed on the bay here Car Air Horn 12v 136db Blast Compact Twin Tone Loud Horns Truck Lorry Boat SUV | eBay

I removed most of the bolt on lug & sloted a piece of U shaped alloy into the remains to act as a bridge onto the starter motor body. That allowed me to get a good angle to clear the header pipes & fit under the starter at an angle. Better pic here of that.

 

Nice Job! Thanks for the reply too. :smile:

Did the kit come with a relay? Was toying with the idea of an air-horn on one of my bikes as some of the south Florida drivers are post-labodimal...

 

Yeah its got a relay with it, all its missing is some wire & connectors to wire it up. Standard spade connectors on the end of the motor & on the relay. I've used seperate compressor & horn units in the past & normally put the compressor in the back of the tail piece under the seat & run the air lines out through gaps in the under tray, then bolt the horns to the side of the rear fender area & face them forwards & down a bit. But becasue the VFR is tailend heavy I thought an integrated unit would be better so long as I could find somewhere to mount it up front.

The unit weighs 600grams, but the old Honda horn was 296grams & attached to the head stock. That is now gone & I'll fit an air baffle under the bottom yoke, to assist with pressuring my ramair intake below the head stock !

 

Well it's been a while as I was working away & only able to do a little at the weekends, but finally got the bike out yesterday. What an amazing difference in braking power & control. Superb brakes now like I remember on my CBR600 I don't normally use the back brake much & this has made the balance of power for go & stopping perfect. Best mod I've done on my VFR, just as Honda should have made it !!!!!

 

Nice write up! I have seen one or two bmw k bikes where the doodes ditched the abs too.

What kind of coolant hoses are those? UK product? I bought a skid-marx windscreen for my Gen 3 bike and was impressed.

 

I Love your carbon fiber rim !! do you have one on the back as well ? and where did you get them ??

 

The hoses are from ASH in the UK, they are not VFR specific, I made my own measurements & ordered stock hoses/sizes to suit.

The carbon rims are BST & yes there is one on the back too. Search for VFR800 10 year refresh part deux & you will see all you need to know.

 

Special note re the air horn, it draws 20amps !!!!! So good wiring & relay definately required.

 

that wheel, mounted on that bike, with those forks, and those brakes....it's probably wondering what it did to deserve that........

 

So what's wrong IYO with that wheel on that bike combination ?

All bikes can benefit from lighter wheels & as these wheels & associated upgrades save over 3Kg from the unsprung & rotating mass at each end, I'm more than happy with the handling
They estimate that these wheels are worth 10+hp for acceleration & then they are better everywhere else, like cornering or braking.

I've asked before about your 6th Gen engine build, do you have any details ? as I can't find a thread for it.

Thanks

 

Princess Norcalboy is really most interested in your rear suspension than your front end loading.

 

Bump for Norcal Boy !