[Mikko Nassi]

The discussion about the CRG brakes in a thread in General talk got me thinking about brakes in general....

Is there really any advantage to be found in modern-day karting brakes?

Not long ago Magura started to market a braking system for karting with a lot of marketing talk claiming that they improve laptimes and make overtaking easier. Many quickly dismissed these saying they were just like any other brakes, while some claimed that they were better.

Now CRG Asia has claimed that the CRG "duralcam" or "dural" brakes are the next big thing which I believe is an Aluminum disk instead of a steel one (weight is about the same as a narrow steel disc), and a floating disc instead of fixed mount - otherwise they are the same as the standard brakes.

My opinion is that getting enough power in kart brakes isn't a problem in any current system - as long as the brakes are working properly locking up the wheels is no problem. Also I've tried a lot of different brakes and I feel that while some feel different I am able to get used to different types of brakes within a few laps and am able to use them just as good as the other system, then it's just down to a matter of preference if you like your brakes to bite really hard with very little effort or if you like them to require a bit more effort for example (some of this can be adjusted as well by changing the mounting of the brake pedal to the system)..

The main aspects that I find are important is having the brakes perform consistently from session to session, and of course reliability of the brake system.

[TJ Koyen]

I agree. I think that as long as you can lock up the rears, the brakes are strong enough. However, some karts have thick brake pads or for other reasons, they have very little pedal length. Meaning that the brakes act more like a switch, they are on or off. I keep running my brake pads down to the screws because I like the long pedal feel. I think it helps you be more precise with your braking.

[CRG Asia]

Hi Guys,

The dural Can is not use a Aluminium disc. It has a coating over it to reduce its spinning inertia while driving thus achieve less weight.

There is a write up about it on the website:
http://www.kartcrg.com/ingl/news_ingl/pg_news.htm

Look at the very last article. You'll know the difference. The dural brakes are allows for a smoother ride.

[RocK]

At Kosmic/Tony brakes have been evolving also. That introduce a self gap adjusting and now doing brake pedals feels.

I tested 04,05 & 06 brake system

the difference in brake feels are:
04= 50%~100% full lock
05= 40%~80%~100% full lock
06= 20%~40%~60%~80%~100% full lock

so driver can been more smother in corners that used a tap of brakes. Thats how brakes improve laptimes. For Kosmic/Tony camp anyway..

[Jules]

ONE of the reasons why CRG has the smaller and now exotic material disc is to reduce the rotating inertia mass which means lighter mass to spin around....ie. improving engine response.

This naturally requires a smaller caliper set up and hence the double caliper configuration - at least seen on the Road Rebels.

Of course, it also give u more clearance to the ground and hence lessen a chipped disc situation. The floating disc tech is not new and gives u a self adjusting feature to compensate for pad wear.

At least the above is what I observed and understand. Daniel, correct me if I am wrong.


I think a longer travel will suit older drivers like me..since we are more used to driving cars.....

[CRG Asia]

Jules,

Yes you are right for most parts about the floating system and also the Lesser spinning mass. But the new Ven 05 System only have 1 caliper. Instead of having 2 smaller caliper with 2 master cylinder it is replace with 1 bigger caliper and 1 master cylinder. The old one UP2000 used to have 2. But the general concept is to achieve better consistency and spinning inertia.

there is also a way to make this braking even better. By using 2 master cylinder to fit 1 brake caliper. I'm told that it gives it an even braking ability. But yet to try it for myself. I was told of this by the CRG dealers in UK.

Daniel

[Mikko Nassi]

RocK that's a good point - a bit smoother when only a tiny bit of brake is needed. This can also be adjusted a tiny bit by mounting the brake cable/rod that links pedal to master cyliner into the higher or lower holes on both sides.

Yeah Jules you are thinking of the 2000UP system which used a smaller diameter thin disc not exotic though, they're back to a slightly larger diameter and much thicker one now - the disc looks similar to what for example arrow karts have. I think TonyKart switched to a smaller diameter disc as well maybe for 06 (RocK?)? Interesting progression there in tk brakes btw.. I think I last used the 05 model brakes, didn't mind them.

True might be good for oldies ... for young kids looking to go into cars less travel is better because formula car brakes also have very little travel and work on pressure more than travel unlike road cars.

The dural Can is not use a Aluminium disc.

Here's what the site you linked to says:

There are two different types of disks available for the VEN 05:

the first one is made of cast iron and has a fixed disk support

the second disk is in aluminum and is coated in a special duralcam material complete with a floating disk support

It also says that the Duralcam disc is the same weight as the Ven-04 brake disc... which I believe was cast iron but smaller in diameter and thickness? That's just why I'm confused as to where the great advantage comes compared to the previous braking system for example - same rotating mass so that can't be the main benefit. Everything about the normal VEN05 brakes and the duralcam version is the same except the disc and carrier, or is there another difference? Do you need special brake pads for the duralcam disc or will the standard ones work? (I read some guys saying that the dural disc didn't work at all so they switched to the standard one - did they use the wrong pads?)

Yeh just to be clear I do see the advantage in reduced rotating mass - however small it is still a benefit, this is one reason why 50mm axles are used over 40mm. But for example there is no difference in rotating mass between the 2000up system and the Dural system, so it can't be any better in that area - but it is lighter than the ven05 cast iron disc of course. Any idea on the exact weight difference Daniel?

By using 2 master cylinder to fit 1 brake caliper.

This is what the VEN04 system was right?

The dural brakes are allows for a smoother ride.

Do you mean smoother under braking or during other times as well?


I like a braking system that allows me to be able to get to just when the tyres lock up and then be able to modulate the braking there.. so far all systems I've tried allow me to do this, some easier than others but I think sometimes it's just a matter of getting used to the feel.

[Mikko Nassi]

I've read a bit more about the duralcam process and the idea is that you can mix for example aluminum with some other cool stuff to make it possible to use it in braking applications for example. So it's basically a composite brake disc - and in this case with the primary material being aluminum. Advantages over iron for example are lighter weight and better heat dissipation.

Seems the main draw back for karting is the high cost with very small gains - which is why CRG has it only as an option. Other manufacturers might come out with it as an option if it is a success for CRG. The technology is not very new with the process from the 80's and for brake discs early 90's.. but I guess now the costs have come down enough for CRG to use it, albeit only as an option.

[RocK]

I think TonyKart switched to a smaller diameter disc as well maybe for 06 (RocK?)? Interesting progression there in tk brakes btw.. I think I last used the 05 model brakes, didn't mind them.

TK/K switch to tiny brake pads for 05 & 06 system. Disc diameter are the same. TK works team testing 07 brake system as we speak. Which going to be used at the world finals. so it was reported.

[Mikko Nassi]

ok must've been maybe 04 then when they switched to a smaller diameter disc (from 200mm+ to 180mm).

[Jules]

From my limited driving experience, all I can say is.....

the smallish Kosmic/TonyKart brake is not what I like cos it overheats easily and this is why u see the factory option of a air duct to the brakes.....

the Swiss Hutless brakes with its quick adjustment for pad wear is a very good and practical system. ( esp for DIY buggers like me )

I never had any overheating issues with other brakes except the Kosmic.....must be my driving style.

[CRG Asia]

Mikko,

No there was no study on the Excat weight difference. The UP 2000 not only uses 2 smaller calipers, it also uses a difference brakes disc from the Ven 05 systems. The ven 05 systems have edges on the sides and are much thicker than the UP2000 for better heat dissamptation.

[Aaron]

jules, i like the fact that the kosmic t8 brakes are self adjusting... never had to put shims! but the pads did wear out very quickly, probably due to running hotter...

i just changed to a birel kart... and the brakes seem to me to be more sensitive than on the kosmic... i was locking up a lot in my first session. i learnt that i dont have to push the brake pedal as hard and quick as i did in the kosmic. They seem to require less force from the left foot than the kosmic.

[Mikko Nassi]

Aaron were the kosmic brakes any crispier when brand new? I find that pretty much all brakes lose a bit of the initial "bite-factor" when they get older despite re-bleeding the brakes and changing pads - probably because the pistons and seals aren't changed as well. I know my mike wilson brakes were shit after 2 years no matter how often i bled the brakes because we couldn't source any replacement seals for the brake system.

No there was no study on the Excat weight difference. The UP 2000 not only uses 2 smaller calipers, it also uses a difference brakes disc from the Ven 05 systems.

Yeah the article you pointed out to said that the new duralcam disc is the same weight as the old VEN04 disc.

It would be interesting to find out the total weight and difference in weight between the normal disc and the duralcam disc on the new system though - do you have both in stock and happen to have a good kitchen scale? No need for a study, just a quick measurement.

Do you know if the duralcam disc requires the use of different brake pads, or are the same pads used for both discs?