Radial Brake Conversion

[Quan-Time]

If you can put on "blue spot" R1 calipers, then these will fit. Else i can make a specific TRX / thunderarse template and check it via someone willing to try them out.

[sanddune51]

Great work Quan! You really must have been bored

I have no real interest in the modern machines that have radial calipers fitted as standard, but have read a few magazine road tests of these bikes. Why do the motorcycle journalists rave about radial calipers?

Are they the technological leap forward in retardation as widely claimed and why so? Am I missing something or are not radial calipers in effect nothing more than conventional calipers (ie hydraulic slave cylinders) mounted to the lower fork leg using bolts in a general radial plane squeezing the same friction materials on to a disc of the same material?

Are the calipers constructed to work on the same principles (using the the same aluminium alloys,machined to the same clearances and using seals of the same materials) as conventional calipers? Am I missing something else more fundamental?
With conventional calipers I'm well aware that some brands and types when matched to suitable master cylinders perform better than others (eg Yamaha "blue spots" versus std. TRX). Does this hold true for various manufacturers radial calipers? Is it generally accepted that all radials give superior performance to conventionals?

I guess in short I'm just asking why radial calipers are superior to conventional calipers and are they not dependent on the rigidity of the fork lower they were designed for?


Mark.

[Killerwhale]

Great work Quan! You really must have been bored

I have no real interest in the modern machines that have radial calipers fitted as standard, but have read a few magazine road tests of these bikes. Why do the motorcycle journalists rave about radial calipers?

I´ve only found two "truths" online...radial was made so that superbike teams etc. could experiment with different sized discs in an easy way. They can also be made lighter yet stiffer.
My interest is that there crashes a ton of later R1´s and egay is swamped with 6-pot radials for a nice price....and they´ll probably outperform old blues.

[sanddune51]

Hi Killer,

The fact that different sized discs can quickly be accommodated makes a heck of a lot of sense together as you say with lighter an stiffer. I'm still not convinced they're a "must have", but will remain open minded regarding their benefits.

Mark

[Quan-Time]

The bolting pattern makes them have less flex. So under heavy braking they are a benefit.

They are generally a touch lighter, which adds to the "unsprung weight" factor. Also as KW pointed out, ability to change disks easily is a bonus.

Another thing is they have 4 brake pads in them, not 2. So its one per piston. My 4 spots have 4 pads also. 2 big ones and 2 little ones. Im sure this could be done in axial mount, but never was for some reason.

[NWS870R]

The clue is in their name 'Radial'

I.E: they are radially mounted rather than erm..bolted on the side? To mount radially with anything that rotates around an axis point (i.e. your wheel axle) means your fixed point (caliper) has to cope with only ONE turning force - the direction of the disc passing thru it (this is what eliminates flex) Structurally speaking it's a much stronger option which means calipers can be made much lighter which in turn reduces gyroscopic effects caused by ever increasing disc sizes (move the weight of the caliper further away from the axle & these forces increase & upset handling)

Conventionally mounted calipers of course have the additional effect of their side mounting - direction of disc/wheel opposed to the direction of their mount bolts & caliper bodies (key word: opposed) they work against each other. Generally the forming of a right angle actually adds strength, in this instance it actually forms the opposite as the rotation introduces 'shear' force to the bolts themselves - radial mounts follow the same plane by facing the axle rather than facing in a completely different direction.

Nothing wrong with conventional mounts tho unless your surname is Crutchlow,Toseland, Rossi or Biaggi, etc? I've fitted blue spots in my rebuild - although i might not be able to stop myself making new lower mounts for my Ohlins to accomodate radials & changing my surname!

[Quan-Time]

yeah, as i said its axial / radial.

with Axially mounted, look at how the bolts would fail. The force of the braking action, if it WAS to break a bolt, it would "shear" them. With radially mounted, there is no shearing action. Its more a bend. Because of this, not as much re-enforcement is required in that area. More emphasis can be put in other parts of the caliper. Thus, they are "stiffer". If you had a camera mounted to the forks, and was to video it in slow motion under heavy braking, you would see different flexing.

For the average street "to and from work, rarely giving it a blast on a sunday arvo thru twisty's" you would NEVER notice it. Same goes for USD forks VS tele's and a good rebuild / springs + valves. So for 95% (this is me inclusive) of EVERY bike rider, you dont "need" USD + radial. Its more wank factor.
With that said, ive done this because "i can".. i have access to all the machines and gear so this cost me basically nothing. Only cost was the brakes and lever.

@sanddune51
I understand its hard to get your head around why its "better". Watch this space and ill give you a visual demonstration in only the way that i can

Many here know this, but I find it REALLY hard to "sit still" and just swollow information as gospel. I have to learn and "do" to understand. Much the way i converted my bike to EFI. I built my unit from scratch (megasquirt), but that wasnt enough. I tied in VERY closely with the dev(elopers) to get it working properly as no v-twin engine had been done. I still tie in (beta test) gear on occasion.
Instead of "buying" throttles that fit, i modded some i got my hands on. Bored them out and made new butterfly's to suit. Etc..
Hell, i didnt know "how" power was always effected by changes, so i built something to measure / monitor that (more on that to come in the following weeks).

Anyway, ive got an idea and a way to show you VERY simply and effectively the differences between all possibly brake setups. Gimmie a week or so to rig it up and make a video for you.

[hjp1968]

Slightly off topic but when are you making an EFI kit for the TRX you must be able to do it for cheaper than a pair of FCR's

[Quan-Time]

The REAL question im getting asked is "when are you releasing a touch screen GPS dash".



check out the upload time, these are well over 2 years old, and actually closer to 3 years. As far as ive been able to search, i was the first person to have a fully stand alone GPS / intergrated touch screen on a bike, which is integral to the bike itself, NOT a "stand alone" unit which others have done.

I did find a R1 with a car DIN touch unit grafted into the tank, plays DVDs and stuff, BUt they retained the normal dash as they didnt hook into it.

Ive done 2 revisions on that, ALMOST went to a 3rd, decided on a whole new hardware setup, ditched that and im part of the way thru using my android phone as the dash. Yup, the bike is now bluetooth and spits out data that way. The phone "clips" into its dash position and connects to the bikes ECU, it logs all data for later analysis, as well as utilising the phones GPS software solution. This way i get the phone functionality all in one convenient "carry away" unit.
It will display realtime gauges, RPM, O2, throttle position, speed, etc...

[HansJ]

As always interesting reads from you QT.

Since the adapters will be bolted to the fork the same way as the originhal calipers, do you reckon you'll gain anything except for being able to fitting other calipers? (I know, the wank factor, but apart from that?

Radial calipers is understandable, but the pumps? I can't for the love of my life understand what's so revolutionary with them? Assuming they have the same leverage as an ordinary pump, what would make them so much better? (Apart from maybe being of higher quality).

[Quan-Time]

They offer different pump ratios and leverage actions. They can be tailored to suit ones needs quite,, err. i wouldnt say "easily", but can indeed by custom set. They cost a bit to change, but is well worth it for perfect setups.

The main reason ive done this is i want SUPER twitchy front brakes. My fingers dont work very well. So i need brakes which are really sensitive and are "too twitchy" because i cant feel much.

[Killerwhale]

As always interesting reads from you QT.

Since the adapters will be bolted to the fork the same way as the originhal calipers, do you reckon you'll gain anything except for being able to fitting other calipers? (I know, the wank factor, but apart from that?

Radial calipers is understandable, but the pumps? I can't for the love of my life understand what's so revolutionary with them? Assuming they have the same leverage as an ordinary pump, what would make them so much better? (Apart from maybe being of higher quality).

I have ISR pump wich are adjustable, insane bite on the one setting and really good on wet tarmac on the other and all in between....

[HansJ]

All good and well about the different ratios and sizes and so (i did write same leverage), but there's nothing in the "Radial" technology that make them superior, or? All of your arguments are also valid for a "normal" pump as well. (I am just someone who hates the latest "must-haves", hence riding a TRX )

Ouch QT, looks nasty. Will it grow out again? (Pythonesque )

[Killerwhale]

All good and well about the different ratios and sizes and so (i did write same leverage), but there's nothing in the "Radial" technology that make them superior, or? All of your arguments are also valid for a "normal" pump as well. (I am just someone who hates the latest "must-haves", hence riding a TRX )

Ouch QT, looks nasty. Will it grow out again? (Pythonesque )

Well, i was astouned over the huge difference in radial vs old school pump...both in stopping power and feel.
Guess it has to do with the power applied goes in the direction of it rather than pushing on the pump to the left along the bars. Really don´t care though....it´s the best mod i´ve made along with stompgrips!

[HansJ]

All good and well about the different ratios and sizes and so (i did write same leverage), but there's nothing in the "Radial" technology that make them superior, or? All of your arguments are also valid for a "normal" pump as well. (I am just someone who hates the latest "must-haves", hence riding a TRX )

Ouch QT, looks nasty. Will it grow out again? (Pythonesque )

Well, i was astouned over the huge difference in radial vs old school pump...both in stopping power and feel.
Guess it has to do with the power applied goes in the direction of it rather than pushing on the pump to the left along the bars. Really don´t care though....it´s the best mod i´ve made along with stompgrips!

I don't argue with that, but i think it has more to do with either better build quality or different ratios rather than in which direction the pump's cylinder goes... I just am the guy who shouts about the emperor's new clothes