E.T.'s Comments

Thanks Will! Yeah with some manipulation the shock will come out the left side of the bike. I am working to improve clearances further in this area to make it even easier to install or remove a shock on the next one (and also increase clearance for shock pumps). This prototype has been great for checking real-world clearances and function as I eventually work my way towards the refined production frame. If you've got bike designs you want made, you don't have to be a good welder, you just need to know and hire the right people to weld it for you. John Caletti did a great job welding the first two prototypes for me and it takes the guesswork out of that part of the bike. Nice to know the welds are solid when sending it on a prototype bike!

Thanks Jeff! If you are ever in the Santa Cruz area and want to try a bike for yourself, I should have a few test bikes available after I launch.

Thanks for the kind words! I am planning on getting out and doing some races next year and should have a few bikes for people to check out at those events. I would also like to have demo rides available in the future once I'm up and running. These would be out of the Santa Cruz area (if you live nearby or are willing to take a trip out here). There will be more info about this on the Contra Bikes website once we launch.

Thanks Hugh! I couldn't have arrived at this bike without all of your hard work, advice, and knowledge you've shared.

Thanks Krispy! The idler pulley is fixed to the front triangle via a CNC machined idler carrier. It doesn't move with the links. Hopefully all the geeking out didn't give you a headache!

Thanks Theo!

I do a lot of the fabrication myself (jig construction, mitering, lathe and manual mill work), but I did have quite a bit of help from Noah of Hillside Frameworks on the fabrication side of this one, John at Caletti Cycles did the welding, Dave at Mather Machining did the CNC work on the links, idler, shock mount, tie-bar, and idler carrier, Jeremy at Powder Coat It did the powder coating, and my friend Hans up in Oregon at Motor Control Technology CNC'ed the chain guides.

F$#king sick edit!!! Proper DH riding right there! Best of luck at the upcoming races George!

Thanks Josh! I remember you from Post Office days...I don't trust my welding skills enough yet so I actually had John Caletti of Caletti Cycles do the tig welding for me. I did all the fabrication of parts including the jigs, and mitering all the tubes, but left the CNC work up to local machinist Dave Mather of Mather Machining. He made the lower link, upper link and idler pulleys that I designed. I had a look at all your projects in the past...Cool stuff for sure! At your height what would you say is your ideal reach and stack dimension if you were to make a trail/enduro bike for yourself? You're well over 6 feet right? I'm still researching sizing demands for taller riders...

Cesar Rojo already has a patent granted on a similar design...https://patents.google.com/patent/ES2670470B1

@ JBSDesigns: Why do you not believe in 3DF Foam? Is this based on real life experience? If so was it with this specific pad? Or a much lighter version?

I too would like to see scientific testing to compare, but this would have to be done by an independent laboratory.

With the 3DF Hybrid model from Leatt I had zero doubts in the material. I actually felt like it had better protection than my Fox launch knee cup which has a hard plastic shell within. I've crashed on many a knee pad and this one did its job as advertised.

I rode the fork as provided to me for the test up until the air piston seal failure. When replacing the air piston I did not pull apart the lower leg on the damper side. On the air spring side it appeared to have 10-20cc's of heavy oil that drained out (looked like 90wt or so). Apparently it's the mixture of lubricating oil and grease? Maybe the SR Suntour guys can chime in about this?

When I replaced the air piston I used 20cc of 10wt fork oil in the lower leg as splash lubrication. They recommend 0wt30 or 0wt20 full synthetic motor oil that I did not have at the time. Better performance could be had with the thinner oil bath potentially. I also used roughly 10cc of Fox Float fluid on top of the air piston as they recommended a heavy gear oil similar weight to Fox Float Fluid.

I'm excited about the future improvements (especially to the air spring and damper) as these tweaks could really help the fork perform to its best. I guess we'll have to wait and see...

The claimed frame weight of the SB66 Comp (full aluminum) and SB75 (full aluminum) are both 7.75lbs.

The bottom bracket I used was the Race Face Cinch BSA30 which can be seen here: http://raceface.com/components/bottom-brackets/cinch-bb/cinch-bsa30/

Thanks Noah!