# V-brake & Disc Weight: A Practical Example



## 251 (May 13, 2008)

I recently swapped the v-brakes on my '08 Eriksen Ti hardtail for discs. I don't really consider myself a weight weenie, but I was curious what the brake swap would do to the weight. I chose BB7 disc brakes and a wheelset that is stronger than it is light. I realize that this is not something a weight weenie would likely do, but here it is anyway:









With v-brakes the Eriksen weighed 10.325kg (22.76 lbs), as pictured above.

The following parts were removed:
- Paul's Motolite brakes (front & rear)
- V-brake bosses (front & rear)
- Old brake cables and housing

- Mavic Crossmax XL wheel, UST, ceramic rim brake (front)
- Mavic Crossmax ST wheel, UST, ceramic rim brake (rear)

- Rock Shox Pop-Loc, cable, and housing​
The following parts were added:
+ Hope Pro II hubs, 32h (front & rear)
+ Mavic XM819 Disc UST rims, 32h (front & rear)
+ DT Swiss Competition 2.0/1.8mm spokes (64)
+ DT Swiss ProLock nipples (64)

+ Avid BB7 disc brakes (front & rear)
+ Avid Cleansweep X rotors, Ti bolts (185mm front & 160mm rear)
+ Avid Straight Jacket brake cable set (full length housing)​









With discs the Eriksen now weighs 10.935kg (24.11 lbs), as pictured above.

The only non-brake related part that I removed was the remote Pop-Loc from the Reba Race. The Pop-Loc, cable and housing reportedly weighs 70-75g. The only other note is that I have the same tubed tires on both wheelsets (same tires, same tubes). The Mavic Crossmax wheels required rim tape as they both had a sharp inner surface and would puncture tubes. The Mavic 819 rims do not have rim tape.

According to the Speedgoat Custom Wheel Builder (my wheels did not come from Speedgoat), the Hope Pro II/XM819 disc wheelset should weigh 1769g. According to Mavic, the Crossmax ST and XL rim-brake wheelset should weigh 1653g. The new wheelset is (on paper) is 76g heavier (subtracting 40g for the rim tape) than the old wheelset, so the bulk of the weight gain can likely be attributed to the brakes. However, none of these wheel weights were actually verified, so attributing weight gain to specific parts is just speculation.

Anyway, now that I have a direct weight comparison, I'm going to try the current tires tubeless with sealant. Other than that, I'll probably leave the bike as-is for a while. Although, I suppose a Ti bolt kit for the BB7s might come later.

One more photo:


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## vladxc (Jan 22, 2009)

As far as I know the floating rotors are not ok for mechanical brakes, as only one pad is working and pushing to the other one... and I know friends that had hope floating rotors and shimano center lock and the brakes destroyed the rotors...

btw, do you know the weight for the rim with eyelets? 

Thanks
Vlad


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## 251 (May 13, 2008)

The Cleansweep X rotors are not floating rotors, just two piece. However, there is a short discussion on floating rotors and BB7s in brake forum.

I'm not sure what the XM819 rims + eyelets weigh, but I'm sure someone here does.


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## egebhardt (Nov 16, 2004)

Nice study. According to you, disc brakes add over 1 pound. Maybe more. I'd say a good general rule is 1 pound. I know when Shimano first released their 2003 to 2007 (965 series) line of XTR components, they claimed disc brakes only added 1/2 pound. I still find that hard to believe. I do like the XTR look and feel so that's the route I went.


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## Broccoli (Jun 11, 2008)

egebhardt said:


> Nice study. According to you, disc brakes add over 1 pound.


Mechanical disk brakes. Lightweight hydraulics could be a good half pound lighter, or better. Disk wheelset has no good reason to be any heavier the rim brake wheelset either.


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## BBW (Feb 25, 2004)

251 said:


> The Cleansweep X rotors are not floating rotors, just two piece. However, there is a short discussion on floating rotors and BB7s in brake forum.
> 
> I'm not sure what the XM819 rims + eyelets weigh, but I'm sure someone here does.


think I read 465+50= 515g


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## 251 (May 13, 2008)

BBW said:


> think I read 465+50= 515g


Mavic states 450g for the rim, but I can't find a weight for the eyelets.



Curmy said:


> Disk wheelset has no good reason to be any heavier the rim brake wheelset either.


I wanted a wider rim, and wider rims are generally heavier. As for the brass nipples, I can't say that I've ever had a problem with brass or aluminum nipples. However, I will say that I much prefer working with brass. If weight were a larger concern, I probably would have gone with aluminum.

I could have gone with another set of Crossmax ST wheels, which would have been marginally lighter and significantly more expensive. However, I didn't want to deal with the proprietary parts, again. That, and the graphics on the rims are pretty gaudy.


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## Slim83 (Nov 2, 2006)

Not totally sure what you are getting at here. A disc brake setup can be almost as light as a V brake setup with far greater performance. The biggest factor is the cost. Disc are going to more expensive for comparable weights. You used very heavy brakes and wheels when you went to disc so they are going to weigh a good bit more.


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## BBW (Feb 25, 2004)

http://www.cambriabike.com/shopexd.asp?id=52415&page=MAVIC+SKREWED+HOLLOW+EYELETS

Cambria says that 40 eyelets are 70g.... will be around 515g (I think that's the weight that I read from Larry -mountain high- if I'm not mistaken)


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## 251 (May 13, 2008)

Slim83 said:


> Not totally sure what you are getting at here.


This is a practical example of my upgrade from v-brakes to disc. There are many claims and statements concerning the weights of discs and v-brakes, and I provided this information as a real example.


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## BadHabit (Jan 12, 2004)

251 said:


> Eriksen


My brother's Eriksen cx was front and center at his memorial service. His other bikes (Mootses) he wanted to be distributed among his friends, but he said "Somehow, I just want that bike to stay here." Wife doesn't know what to do with it.


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## 251 (May 13, 2008)

That is a difficult situation. I'm not sure what I'd do. 

Personally, I'd like to leave my Eriksen to my brother, and similarly, I'm not too worried about what happens to the rest.


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## kramnnim (Sep 2, 2007)

Dave...your bike looks familiar. Were you the one who posted about your build (with pictures as parts arrived in the mail) on the VWvortex forums?


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## 251 (May 13, 2008)

Yes, that would be it. Here is The Car Lounge thread from 2008.

Aside from the new wheelset and brakes, the Eriksen hasn't changed much. I've been through several tires, and a few small parts (rear derailleur, handlebar), but nothing major.

When I had the frame built, I acknowledged that I may want to go with disc brakes at some point. I'm glad I had the tabs put on the frame.

This was take just before my first ride (from the above thread):


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## kramnnim (Sep 2, 2007)

Ah, thought so. Enjoyed that thread.


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## Megaclocker (Sep 28, 2005)

A nice hydraulic disk brake and a wheelset of the same weight as your previous one would have made your bike maybe 0.5lbs heavier.

Mechanical disk brake are crap compared to hydraulic.


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## gmats (Apr 15, 2005)

vladxc said:


> As far as I know the floating rotors are not ok for mechanical brakes, as only one pad is working and pushing to the other one... and I know friends that had hope floating rotors and shimano center lock and the brakes destroyed the rotors...
> 
> btw, do you know the weight for the rim with eyelets?
> 
> ...


According to what I weighed on my scale:

54 grams for 32 eyelets
450 grams for the rim.


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## gmats (Apr 15, 2005)

Aloha,

That's a great comparison. I did this back in 2002 with my Psycle Werks when I was hemming and hawing about going to disk brakes. Back then I was figuring it added about $500 to the price of a bike and about a pound. My how times have changed, the price of reasonable performing components have sure come down in price with not much penalties in weight.

That's a great looking bike you got there and I know you certainly could have saved lots of weight with the wheels and brakes. The wheels are on the heavy side (but extremely durable) and the brakes are no nonsense will always work pieces. I've speced these on a couple of my friends' builds. With that said, in the end, you have a no nonsense, reliable build.

So here's what I had back in 2002 when I finally converted my Psycle Werks from XT V's to Hayes Hydraulics.

Brake Levers	Hayes - Included with brakes	0	
Front Brake	Hayes Hyd - Caliper/lever/hose/bolts/pads	324	
Rear Brake	Hayes Hyd - Caliper/lever/hose/bolts/pads	324	
Brake Rotor	Hayes - Pair with bolts	256	
Brake Adaptor	Hayes Fork Brake Adaptor	15	
Brake Pads	None - Included with Brakes 
919	g

Brake Levers	Real X-Levers, blue	128	
Front Brake	Shimano XT BR-M739 V-Brake - No Pad weight	185	
Rear Brake	Shimano XT BR-M739 V-Brake - No Pad weight	185	
Brake Pads	WTB Dual Compoud	28	
526	g

*393 grams difference. *

Tubes	Torelli Xtra Lite, Schrader, pair	288	
Front Hub	Chris King - ISO Disk Front	166	
Rear Hub	Chris King - ISO Disk Rear	305	
Front Rim	Mavic X 317 Disk - Silver	395	
Rear Rim	Mavic X 317 Disk - Silver	395	
Front Spokes	DT Revolution	128	
Rear Spokes	DT Revolution	128	
Nipples	DT Alloy, blue, of 64	20	
1825	g

Tubes	Torelli Xtra Lite, Schrader, pair	288	
Front Hub	Chris King Suspension, silver	107	
Rear Hub	Chris King, Roller Clutch, alloy Cassette, silver	250	
Front Rim	Mavic X 517, silver	395	
Rear Rim	Mavic X 517, silver	395	
Front Spokes	Wheelsmith XL15 1.8/1.5mm (15/17 gauge), set of 32	126	
Rear Spokes	Wheelsmith XL15 1.8/1.5mm (15/17 gauge), set of 32	126	
Nipples	DT Alloy, blue, of 64	20	
1707	g

*118 grams difference. *

Total weight difference: 511 grams (about 1.1 lbs).

In the end, an incredible world of difference in performance. Back then, was it for everyone? No, probably not when you factor in the expense and extra braking which a lot of people didn't need. Today? Cost is a no brainer. Most people around the street or just starting out probably don't need extra braking performance but why not get it?

Anyway, thanks again, great looking bike.

Aloha,
g


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## 251 (May 13, 2008)

Thanks for the comments. Although, I'm a little surprised that I didn't get more flak for my brake and wheel choice. In the past, I've certainly received a far more vitriolic response to my archaic rim brakes, and I think I genuinely offended some by having v-brake bosses on my frame.

Anyway, I'm not convinced that I "need" the 185mm front rotor. I'm considering swapping the 160mm to the front and putting a 140mm on the back. I suppose this would be akin to putting a carbon saddle on a downhill bike, but I'll probably try it and see how it feels.

As for the tires, last night I replaced the tubes (standard 2.0" tubes from Performance) with some sealant. I used JetBlack sealant, which appears to be a close Australian approximation of Joe's or Stan's sealant. I'm currently living in Australia.

As an aside, while searching for sealant, I came across the Stan's tubeless kit (this one), which was $215 AUS ($193.50 USD) at a local shop. I was a little shocked, especially when I bought 250ml (~8.5 oz) of the JetBlack sealant (not a kit) from another local shop for $8 AUS ($7.20 USD).

So far everything looks okay, although I did notice a small rip in the sidewall of the rear tire. I used a total of 100-120ml (~4 oz) of sealant, added two valves, and removed two tubes. So, I'll now conservatively estimate that the total weight is 250-300g less than with tubes, which would put the bike around 10.7kg (23.6 lbs).


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## Manicmtbr (Jan 26, 2004)

You can drop a little weight from your brakes too. When those pads wear out, you can replace them with Kool Stop pads with aluminum backing plates. Origin 8 has some really light rotors available for great prices. A 160MM version weighs 83 grams (no idea what your current ones might weigh).


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## gmats (Apr 15, 2005)

251 said:


> Thanks for the comments. Although, I'm a little surprised that I didn't get more flak for my brake and wheel choice. In the past, I've certainly received a far more vitriolic response to my archaic rim brakes, and I think I genuinely offended some by having v-brake bosses on my frame.


To each his own.........that's just a bummer that someone would be so opinionated about a bike that they don't own or personally ride.



251 said:


> Anyway, I'm not convinced that I "need" the 185mm front rotor. I'm considering swapping the 160mm to the front and putting a 140mm on the back. I suppose this would be akin to putting a carbon saddle on a downhill bike, but I'll probably try it and see how it feels.


Well, there you go. Once again, it's all up to you. I myself do a lot of downhill trail riding through some pretty serious technical stuff. I've done fine with a 165 mm rotor for years. I was disappointed when I put my Magura Thor fork on the bike and it had to run with a 185 mm rotor.



251 said:


> As for the tires, last night I replaced the tubes (standard 2.0" tubes from Performance) with some sealant. I used JetBlack sealant, which appears to be a close Australian approximation of Joe's or Stan's sealant. I'm currently living in Australia.
> 
> As an aside, while searching for sealant, I came across the Stan's tubeless kit (this one), which was $215 AUS ($193.50 USD) at a local shop. I was a little shocked, especially when I bought 250ml (~8.5 oz) of the JetBlack sealant (not a kit) from another local shop for $8 AUS ($7.20 USD).


I've been running a version of tubeless for many, many years. I started with the original Stans's "kit". It was pricey and kinda finicky but worked once set up. I learned that there were certain tires the sealant just worked with and some difficulties through out the years (rim/tire combinations, don't use CO2 to inflate tires etc.). I've always preferred schrader valves so I've since gone to "ghetto" tubeless which involves stretching a 20" tube over the rim as a "rim strip". Works very well and extremely low maintenance.

My eyes popped out when I saw $215 AUS. Geez, that insane. Look up "ghetto tubeless on the wheels/tires forum section and do it that way. It works great and is much cheaper with just using the "Stan's" sealant (or what ever other recipe sealant you decide to use).



251 said:


> So far everything looks okay, although I did notice a small rip in the sidewall of the rear tire. I used a total of 100-120ml (~4 oz) of sealant, added two valves, and removed two tubes. So, I'll now conservatively estimate that the total weight is 250-300g less than with tubes, which would put the bike around 10.7kg (23.6 lbs).


Excellent!! Yeah, the debate's out on whether the tubeless set up is lighter with that liquid moving around in your tire but I will never go back. I've ridden for so many years with out a flat of any kind, let alone pinch flat. I am able to run lower pressures (and normal, higher when needed) without any kinds of fears of pinch flats. Tubeless certainly is a little more work up front and a little maintenance from time to time (once very 6 months or so for me) but it's well worth it. Good luck with that.

Oh by the way........My Psycle Werks has the old brake bosses etc still but I'm running "adapted" Avid Juicy 7 hydraulics on that bike now. Who cares what it looks like, just as long as you get out and ride and enjoy...........


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