AlfaW

Hello!

I did 200,300 km brevets. On 20 of May in a few weeks I'm going for my next challenge - 400 km. My physical form is good, as i do sport constantly like running/cycling etc.
I did all my brevets with my 2004 y. Merida MTB bike with 26' wheels. The next one i will go also with this MTB bike. I wonder - I'm the only one crazy , who do brevets with such bike? Most people use gravel/road bikes with big wheels for fast spinning. I will have to use much more energy and power on MTB bike to cover 400 km distance, then those, who cycle with proper fast bikes.

Is there anyone, who cycle 400 km brevet with old MTB bike?

Thank you

GhostRider62

Mtb on brevets is not commonly seen. If you mount fast road tires, it might not be too bad if the route is not too hilly. You will work harder compared to a road bike but might be more comfortable as well. Good luck on your 400K. I did 200k once on one. It isn't for me.

mrv 

https://www.renehersecycles.com/oreg...od-or-madness/

I dunno how you guys keep going after say.... 130 miles, but much more than 100 miles, not for me.
That said - Jan Heine is finding 26in wheels as a solution for his dirt / pavement style of riding. The bike he's on in the article is something like $14k. I find my touring set up (75~100 miles a day) requires a lot of experimentation. My primary touring bike a circa 1990 RockHopper. 26in wheels, of course.

unterhausen

A whole contingent of Thai riders rode PBP on fatbikes, which is a step up in difficulty. I recall in 2011 on PBP that I saw a lot of mountain bikes. I don't remember that many in 2019.

Assuming you have road tires on it, the big thing is that it's hard to get out of the wind on a mtb.

GhostRider62

The PBP results database has a mountain bike category (VT.....velo toute terrain). There were zero mountain bikes listed in 2019. I also did not see any out there but did see several fat bikes in the Loudeac and Tintiniac area when I was on the return. I did see a fat bike between Loudeac and Carhaix around the secret rest stop. Very doubtful even the one up in the hills finished in time.

unterhausen

I vaguely recall there was one finisher. Maybe they didn't register as VTT?

I saw one of the fatbikers admiring the view from the top of roc'h Trevezel on my way back and they certainly weren't going to finish on time.

AlfaW

Any recommendations for fast rolling tyres for 26'?

Polaris OBark

https://www.renehersecycles.com/prod...tires/26-inch/

I have the treaded ones, but the slick ones would probably be what you want.

GhostRider62

If you have 559 sized tires (sometimes people call a 584 a 26 inch), Rene Herse is probably your best bet in a traditional chevron road tread. In 584 size, I think both Continental and Schwalbe make a 32 mm in the GP5000 and Pro One, respectively. I could be wrong but going from memory. Two tires like this (Herse, Conti, Schwalbe) will save you hours on a 1200k compared to a traditional Mtb tire. (don't make me calculate....)

kingston 

RH will be the best tire, but they are expensive. I use Paselas on my tandem with 559's and Michelin Wild Run'rs on my recumbent. Both acceptable and inexpensive tires that I have ridden on 400k's. Michelin, Schwalbe and Conti all have a few 559 road tires in various widths and price-points. There aren't a huge number of options so once you pick your width and price range it really narrows it down to just a few options.

Tourist in MSN

I am not going to say they are fast, but I have used 40mm wide Schwalbe Marathons (with Greenguard) for touring on pavement with one of my 26 inch touring bikes. This was with my camping gear on the bike, worked great for that. You probably would have to order on-line.

More on that tire here.
https://www.bicyclerollingresistance...-marathon-2015

On that, there is an error where they say for available sizes:
47-559 (26x1.75)
40-622 (26x1.50)
32-559 (26x1.25)

Where they say 40-622, since they also say 26X1.50, I am pretty sure they mean 40-559 which is the size that I have used for pavement touring.

I have no opinion on their 32mm width Marathon, but I have 32mm tires (different brand and model) on my rando bike.

Marathon is a wire bead, does not fold.

Note that there have been a whole series of Marathons, so I specified Greenguard to be clear which specific Marathon I was talking about here. I have also used Marathon Duremes, Marathon Extremes, and Marathon XR, all three of those are now discontinued.

downtube42

Re: 26" (559) tires, I ran Primo Racers at 1.25 aka 32mm on my recumbent, on many brevets. Not the wheelchair variety. Some call them flat magnets, but i ran them on two PBPs and multiple SR series with few flats. They are wafer thin, and light.
https://www.modernbike.com/primo-rac...6-x-1.25-black


More recently, I used Continental Grand Prix at 28mm. Mostly because the primos were getting hard to find.

AlfaW

I will check today what we have in our local stores. Will be looking for slik/semi-slik tyres. From 1.5 to 1.9. Previous brevets i did on Maxxis Larsen TT 2.0.

Do you think there is a noticeable difference in speed between 1.5 slik and 1.9 semi-slik tyres? I'm not sure - should i opt for slik or semi-slik tyres. I would better opt for semi-slik to be able to ride on unpaved roads as well, then slik only. But if there is a noticeable improvenet in speed with fully slik tyres, then i might go for 1.5-1.6 slik tyres.

HTupolev

Within the range of common wheel sizes, wheel diameter really doesn't have a large effect on performance on pavement. At least not directly: availability of performance-oriented equipment is a tangible hindrance.

Depends on the particulars. "Semi-slick" can mean a lot of things, and tread pattern alone is only one of many factors that influence tire rolling performance.

For example. Schwalbe Marathon Plus has a near-slick tread pattern, but it's a beefy tire with long wear life and extremely high resilience to flats. The material that makes the tire tough also consumes a lot of energy as the tire deforms against the road surface, resulting in very high rolling resistance. As a consequence, it's actually slower-rolling than many mountain knobbies, let alone performance-oriented road slicks.


What sorts of surfaces do your unpaved roads have? Slicks perform poorly on snow, mud, and wet vegetation, but can be pretty reasonable on rocky aggregate. On my gravel bike - a 1984 Stumpjumper converted to drop bars - I usually run ~2.1" Rat Trap Pass ELs from Rene Herse, which are slicks:



If the bike was primarily used off-pavement I'd probably run a mild knobby all the time, but the bike sees a lot of pavement.

What particular slicks and semi-slicks are you looking at?

AlfaW

I currently have brand new unused 2 semi-slik tyres:

Shwalbe Marathon Mondial 2.0
Maxxis Pace 2.1

I have checked slik tyres in local store today, and I was told, that probably there will be no much difference in speed between semi-slik and slik.

The question I have now:

Should I keep my old mountbike Maxxis Larsen TT 2.0 and do my brevet using this tyres or if I put those 2 semi-slik tyres I mentioned above - I will get improvement in speed?

Larsen tyres already used, so protection is kinda weared off and they look like slik tyres somehow. Or new semi-slik tyres is still better then old used mountain bike Larsen TT tyres?

mrv 

- is that the original paint? I can't tell in the pic, I'm too lazy to search your posts
- if re-painted, did you go powder coat or wet paint?
Last: mmmmm..... bi-plane fork..... nice.......

Chris Pringle

I have never attempted to ride a brevet on a MTB, although several members of our club here in Mexico have done it. The longest distance a few have completed is 400 Km. By the time the 600 Km rolls around, everyone is on road bikes.

Regarding wheel size, it absolutely doesn’t make any difference. I am one of the few ones with a 26” wheeled rando bike. I have run road tires from René Herse and Schwalbe between 1.5” and 1.75”. I’d have to say Schwalbe Marathon Racers are my personal favorites - they roll quite fast and offer excellent puncture resistance on a timed event.

My bike in rando mode:


In gravel bikepacking (touring) mode with knobby tires:


And it took me safely over the finish line and within the time limit at PBP 2015 :

Bent4life 

I've been riding a Ti Aero recumbent for 5 plus years now. The bike comes with 650C. With limited 650 tire selection I run 559 (26 inch ) wheels. Continental makes a 559 x 28 Gatorskin and the original Grand Prix. IMHO the Grand Prix is the best 26 inch tire for low rolling resistance and comfort. You will have to dig to find them but its a great tire.

Carbonfiberboy 

The only real downside of MTB is MTB tires. So what if the frame is a little heavier? Tire diameter makes no real difference. The only real drawback is limited hand positions. At least you have many close ratio low gears, which is good.

For tires, get slicks. MTB rims are usually wider than stock road rims. Measure the outside width of your rims and get a tire of that width if possible. My wife has been using a Bontrager SR1-1.25" on her trainer bike for years, lots of use, very little wear. 345g.
I don't think it's still in production but is still available: https://www.tritoncycles.co.uk/compo...e-p6443/s13798

Otherwise, my choice would be the Continental Contact Speed in 28mm, 425g

GhostRider62

OP.....report back on your experience with a Mtb bike on the 400k.

There are two huge compromises. Lack of many different hand positions and massive aerodynamic drag sitting upright, especially into a headwind.

I considered riding retrofitting a Mtb bike with fast tires and some sort of more comfortable handlebars but I was too slow. Then, I modified a 650B conversion bike for a more upright position and although it was slow, I could do the brevet within the allowed times andit was pretty good. To be honest, the range of bikes is pretty wide ranging from carbon racing bikes to steel framed super touring type bikes that would probably have been at home at the TdF 50 years ago. The added weight of the Mtb isn't trivial but it isn't determinative either.....the aero drag and limited hand positions are significant limitations on the longer distances.

unterhausen

50 years ago was 1972, the biggest differences are that in 1972 the bikes had better paint jobs. And the riders actually used their drops a lot of the time.

GhostRider62

Wheelbases were a little longer, the chain stays were a little longer, the fork rakes were a little different and the fork crown was not so close to the front tire. You could fit more tire. The biggest difference for me at least are the seat tube angles of modern carbon frames, they are steeper than the old steel frames and comfortable setback is a challenge. Measure an old Merckx or Masi GC. These old steel racing frames are what I would call a Century geometry or even super touring geometry compared to the geometries of carbon frames that followed, which ostensibly due to the cost of molds, most Mfgs do not offer as many sizes and the back half triangle is the same on all sizes. And if you are a big rider, you can pick a 58 or jump up to a 61. It is only recently that racing bikes could fit 28 mm tires whereas many (most??) 40-50 year old steel frames can easily take 28 mm tires.

Drops are not the fastest position anymore with flat top and narrowed bars. The cross sectional area of the leading edge of the drop isn't even round on many carbon bars. 36 or 38 mm width are very common. I am using a flat aero topped carbon bar with a suspension stem for comfort and it makes a world of difference. The transition from the brake hoods to the bar is nice flat spot to park your hand and the flexible bars take a lot of road buzz away while the stem elastomer helps on larger hits. The hand discomfort is why a Mtb bike and also moustache bars did not work for me, they are fine for shorter rides and riding 100km into a wind sitting upright was all I needed to know that a road bike was better for me. A stronger rider might not care about an hour or two lost to the wind.

Tourist in MSN

In 1972, freewheels with five sprockets were the norm on frames with 120mm rear dropout spacing, lugged and brazed frames were the norm but the more expensive were silver soldered lugged frames. Clincher tires that were 27 inch (630mm) were the norm, typically 27 X 1 1/4, the tires were slow, tubes were Shrader. A lot of bikes were sold with tubular tires simply because the crappy clinchers of the day. Indexed shifting was just something that you would dream about, the few attempts to make indexed shifting was not successful enough to obtain a foothold in the market. Unless you spent a fortune, your bike weighed a ton. The better handlebar tape was cloth, the plastic handlebar tape that was sold on most bikes was dismal but looked nice to the marketing department. The galvanized non-butted spokes were not so great. Nuts and bolts, almost nothing used allen wrenches and you often rounded off the flats with adjustable wrenches. It was a rare bike that had brazed on fittings for water bottle cages, the typical cage was sold with metal straps that strapped the cage to your frame, the nuts and bolts were galvanized and were rusting in a few years. Your Tour de France wonder bike still weighed over 20 pounds with either a Brooks Pro or an Ideale (spell?) leather saddle depending on where the bike was made. And I have not even started on derailleurs yet. LEDs for lights?, what is that?

HTupolev

It's hard to guess without testing, but none of the tires that you're bringing up are designed to put much emphasis on paved performance.

If your knobbies are worn bald, it might not be a bad idea to change them out to prevent tire failure, if nothing else. Depends on the tire, but many knobbies don't have much tread depth beyond the knobs.

It was powder-coated by the previous owner.

Darth Lefty 

Plenty of people put 1.5 inch slicks on 26ers for commuting. I’m sure there are still 100 options of tires in that size. It does help to put on a bigger hybrid crankset like 48 38 28. With the 42 32 22 cranks from the 104bcd era, smoother smaller tires put your cruising gear right around where you want to shift between the middle and big ring all the time. SRAM makes an 8 speed cassette with short shifts at the high end and big shifts low that works great with this larger crankset size.