La Bourde

Be careful, they wrote "30% pressure increase". That does not imply 30% power increase (I guess the brake power increased though). Do the Hope brake pads have play within the trial caliper? I think the current brakes are powerful enough, the problem remaining is more the exposure of the rotor and the play on a 26" bike.

Regarding 2): Screwed-on freewheel or sprocket imply per design a misalignment. This is why splined freewheel of sprocket are superior (in theory at least). The same issue is present with bottom bracket. But if the difference in chain tension is small, it is fine. Regarding 3): What freewheel are you using? Those with a lot of engagement points (120 or more) have a lot of drag, due to stronger springs. They need to be broken in too.

There was also these Ruthless prototype:Here I found this pic too: but to be honest, now with the current disc brakes, I think the problem to address is no longer the power, but more the play due to the brakepads. So a bigger diameter of rotor .. I don't know. And now there are 220mm disc rotors available (for downhill use)

Hello, I used one on my rear wheel in combination with tube. I posted a thread on this forum, to share my experience. Now after several months, I noticed many drawbacks: high rolling resistance, lack of protection from hits coming sideways, no extra protection of the sidewalls (I used light tires - schwalbe table top - the side walls did not last long and they do not give enough support, so I prefer tires having a heavier casing without insert) Depending your type of riding, you may be OK with, but I won't recommend these for street trial, due to the rolling resistance.

Nice! Never understood why Giant designed the rear disc brake mount this way... Can't imagine it lasts long. The Ashton fork looks massive!

I think these are "standard" frame rear ends. Look for DR10C dropouts. I am not a big fan of Marino due to the apparent built quality, but at least this one looks nice.

To me, you should not have any concerns. The marks are not deep. I expect this condition in case the bike was not well maintained/protected. I assume the previous rider landed several times on the chain, that then slapped against the frame (failed sidehop or pedal up). Or maybe he rode with not enough chain tension. He could have protect this tube, using a small part of rubber or some Velcro.

Cracked at the chainstay? I had really a lot of fun on mine!

Hi, so I eventually rode on Sunday, the weather being better that forecasted. Bleeding with the Putoline was not a problem at all. It is almost transparent. I am not sure if it is related to the change of brake fluid, but I had a very nice session on that day. I had the impression to have a better control on the rear wheel. Previously the brake pads came back really slowly. The rear brake felt much better than with the original Magura oil filled in: it seems that I required less force to actuate the lever, which is a nice improvement too. Overall, I really appreciated the change and did not find any drawback. There is a small improvement compared to the Shimano oil (the front lever still uses Shimano mineral oil). The viscosity of the Putoline HPX is definitively less than the Shimano one: the lever required less force and it come back faster. Unfortunately I never run water (that damages brakes) or Jistsie/Trialtech brake fluid, so I can't compare with. My recommandations: if you already own Shimano oil, use it. if you want something better: Putoline HPX 2,5 (or maybe Jitsie/Trialtech brake fluid) if you don't own Shimano mineral oil, go for the Putoline if its price is OK (I paid the same as for Shimano oil) the viscosity of the original Magura oil or LHM+ is higher, so prefer either Shimano or Putoline

So I have bled my rear HS33 with the Putoline oil. The front brake uses Shimano mineral oil. Compared to the original oil, the Shimano one is already much thinner, one can really notice the difference, the lever comes back much faster. With the Putoline, this even more the case, but the difference is less between Putoline and Shimano than Shimano and the original oil. The lever is really easy to activate, there is almost no resistance. First ride this week hopefully.

I built recently a street trial bike based on a octane 01 spark DJ/park frame. It is so versatile, it is a lot of fun. Manuals, bunny, rotations... A lot of tricks are much easier than with a comp bike. TGS are more difficult, but when you are riding street, you don't care that much. When I am riding my pure comp bike, I really miss the rolling aspect of riding. But it is a nice device to train and to have fun in a different way. I think street trial bikes will continue to evolve and merge with park/pumptrack bikes. The only part missing is a gear system that is not exposed. I really enjoy this video, nice riding!

Thanks, that sounds great. You are right, the Putoline HPX is a synthetic oil, not a mineral oil as I wrote before. I used LHM+ years ago and I can confirm your feel. It was thicker than the Shimano disc oil for example. I think the difference of viscosity is easier to notice with HS33. The system uses a lower pressure than disc brakes (the master piston diameter is 14mm on HS33 compared to 9mm on some Shimano disc brakes, so the surface difference is huge, more than twice)

Found the chart again, but not sure this link works

Thank for your answer. It is a synthetic oil, used in fork suspension. 2.5 means here the "viscosity" of the oil, it is its SAE value (SAE=Society of Automotive Engineers). The lower the value, the less viscosity. But this value is not really a reliable metric, it is better to know the cSt (kinematic viscosity in centistokes) at 40° for example, which is really low for this oil (can't find the chart I saw). So it is not a DOT based oil. As I wrote, some people use it also to fill Shimano brakes, which use mineral oil, so I will be fine.

Hi, I recently bought a(n used) pure competition trial bike. It has a new HS33s with the original Magura Blood fluid. Many many years ago, I owned already one (Koxx code) with HS33. Later I bought a comp stock with disc (Avid juicy in 200mm, about 15 years ago!) I was never a big fan of HS33. And having - good - experience with discs, I don't really understand why pure competition bike still use HS33. It might be lighter, less exposed and have less play but with disc you can nicely modulate your braking and they are now powerful enough (with the right brake pads). But I digress. I struggle to get used to this on/off behavior of the brakes. I had mechanical and hydraulic discs on my street/trial (I have also a frame with Vee) and I am used to the progressivity of the bike, I let roll the bike a lot. I supposed too, that the lever does not come back fast enough, which amplify the on/off issue. I recall that many riders used water to bleed their magies. Recently I saw Jitsie and other brands sell a special oil (but they surely get it from somewhere). So I decided to bleed the front brake with Shimano disc oil, that has a really low °CST. It feels much better now. Today I ordered Putoline HPX 2.5R oil and I think I will bleed the rear brake with. I read indeed that it has one of the lowest °CST on the market, even better than the Shimano oil. This oil is used by some German guys to fix the moving bite point of the Shimano disc brakes. I will let you know how it feels once done. It could be a nice alternative, cause it is cheaper that the Jitsie or Trialtech brake fluid. Do you have some experience with this kind of fluids? Do you know the CST values of the Jitsie fluid or Trialtech? Did you ever encountered leakage due to usage of a low viscosity fluid? For those that were used to disc brakes and now ride HS33, did you have to adapt to them? I mean I had not problem with Vees (the rims were not grinded though)

Nice! Small concern: I think it makes the frame alignment more difficult due to the length of the weld. On some dirt bikes (YT, Norco, DMR, Eastern), there also a yoke with a similar form. But it is not CNC, it is one piece hydroformed piece of steel that goes to the rear end of the frame! Regarding the brake mount: thx, I did not know that the MT6 was available in direct mount. On one hand, I love when someone tries something different On the other hand, as an engineer, having only one solution available on the market is a bit dangerous -that is why I tried to buy bikes without special solutions/standards.

Interesting and weird at the same time. The yoke of the chainstays is just incredible... it seems to be CNC'd. Don't want to know the cost of it (steel is really expensive to machine) Some of the tube shapes is unconventional, I don't think you can order this kind of shapes, so it will be interesting to know how he got those. Also the frame has a direct mount disc brake. This is typically used on gravel and road bikes. Not sure what calipers are available in this standard and how much power or modulation you can expect from them. And I agree about the fork brake mount. Really nice project though and I love the look of it. I owned an Explozif Zon'up. It was a perimetric brazed steel frame. It broke twice! The material of the frame has not the major influence on the frame behavior. The specific modulus from steel, aluminium or titanium is almost the same. That is why the design of the frame is much more important. But one has to take in consideration that huge diameter steel tubes will be very easy to dent (to maintain a good weight you have to reduce the wall thickness ), so it is difficult to build a stiff frame (due to the second moment of area, when the radius of a tube doubles, it gets 16x stiffer) with this material. Now if you compare the chainstays and seatstays of a Crewkerz to the ones of this frame, you can imagine that either this frame shall be pretty heavy to get the same stiffness or it won't be as stiff as a Crewkerz (which has much wider chain- and seatstays)

Hello, can't really help you but I have the same question for a cleep2 in 26". I saw Jistie produces one downtube protector but not sure if it fits. Tarty sells also this one It seems to fit the 20" version of the cleep 2, but my 26" is 64mm wide and the protector won't fit. I was also envisaging to make my own using some kind of fibers (carbon, glass, etc.), but I have no experience with.

I also changed the cable brake housing for some Odyssey Slic. Can't recommend them enough! The glow in the dark effect is quite nice too!

Hey, don't know the year exactly. But the same frame was still sold by Octane01 last year. Now I ride a RS Reba with 80mm of travel and I really like the versatility of this build.

I am a big fan of 5.10 shoes for MTB, but I don't like any of them for trials or street/trials riding. Too stiff and too much grip, I like to be able to move my feet. Did 5.10 stiffen the sole of the freerider? I mean they were known to be not stiff enough...

I have some BB7s on my Octane01. Can't feel any sluggishness difference currently (around 0°C), but I have to say, that I don't feel my fingers anymore at this cold temperature

I can only scroll down to the Giant, then it is over: a pop up is displayed and I can't scroll any further. Maybe you can try with the "Private" or "Incognito" modus of your web browser.

I don't have instagram but the few I can see look already amazing! Would like to see you whole collection for sure. Do you have an Exploziv Zon'up? A Sunn Xircuit Maxx Trial?

Just want to show you the last street/trial bike I built, because I really appreciate the result. The aim was to have a cheaper bike, with reliable/low maintenance parts. The frame is an (used) Octane01 Spark. It is basically a skatepark frame, from the NS Bike sister brand. Its price is reasonable (less than the rear wheel). It is on the heavy side, but I did not expect the bike to ride that well. To me, it is like a low budget Arcade with 26" wheels. The geometry is: wheelbase: 1010mm chainstay: 381mm bb height: around 350, so about +20mm head angle: 74° the fork has an axle to crown distance of 445mm and can be replaced by a suspension fork with 80mm travel. It has a BMX bottom bracket and crankset, 25T/20T gear, BB7 brakes. I'll swap the fork for a Reba with 80mm travel in a near future. It does not really fit the original concept, but I think the bike will be even more versatile. I decided to ride a Hope rear hub to be able to ride several gears, but this is not the case currently (it should not be a problem to put a mech on the frame). Hope it can inspire you for your next build.