jsudar
Well-Known Member
- Location
- Cedar Hills
Progress has slowed on this project, but it’s still moving forward. Had to take a little beak to build a couple custom bicycle frames. Some of my kids were feeling left out because they didn’t have a full custom frame that dad built in the garage.
Got a 48t rear sprocket (gold to match the rotors). Because of the extra travel the swingarm will see, I didn’t want to drop a tooth on the front sprocket, so I upsized the rear to help keep the chain off the swingarm.
Like Gravy said above, if I’m not planning on ripping around at warp speed all the time, low gearing makes it lots more fun. This was partially determined when I decided to see if my S4Rs would actually do the 155 MPH it’s supposed to do. Turns out, I can’t go that fast. I chickened out around 125 or 130 because I physically couldn’t hang on anymore. The wind load on a naked bike at that speed is incredible. Fairings are important. And 100 is plenty fast.
So the front end is basically finished, now I need to figure out how to get 200mm of suspension travel out of the rear. I toyed with the idea of ditching the linkage and using a matching KTM SMR PDS shock, but that was going to be major(er) frame and swingarm surgery. I scoured the Öhlins site for hours, since they have shock stroke and eye to eye data trying to find a factory shock that would give me the right travel and work with the existing linkage. The closest I could find was a Desert Sled shock at 81mm travel and 335mm eye to eye. But it only had an eyelet at one end and a yoke at the other. I needed eyelets on both ends. And it wouldn’t be valved for my application. It was looking like I needed a custom solution. I found a lot of European companies (a couple in Italy, one in Sweden) that could maybe build me a custom shock, but it was $$$ and a serious language barrier problem. Then I found RaceTech in Southern California. They make full custom shocks— any size, any ends, whatever valving I need. Super cool to work with and I didn’t have to learn Italian. And not as expensive as I thought. Still not cheap though. So, before I committed to having a custom shock built, I decided to verify it was going to work at all and I built my very own custom shock out of square tube. #mockshox![46882E86-5F39-4814-98AF-6508EF31A014.jpeg 46882E86-5F39-4814-98AF-6508EF31A014.jpeg](https://www.rme4x4.com/data/attachments/117/117913-7e497c397af8911d2cc285a74f42f548.jpg)
![1F44EF54-FC31-4678-9A71-FA22FAEB39D5.jpeg 1F44EF54-FC31-4678-9A71-FA22FAEB39D5.jpeg](https://www.rme4x4.com/data/attachments/117/117914-4a712ce24f81d98ab5a6a617f237ba44.jpg)
![224F9672-4D2B-4D07-A20D-A5ECF649AAC6.jpeg 224F9672-4D2B-4D07-A20D-A5ECF649AAC6.jpeg](https://www.rme4x4.com/data/attachments/117/117915-5b83d769d7d39869f6ebf1a033ab0d58.jpg)
Got a 48t rear sprocket (gold to match the rotors). Because of the extra travel the swingarm will see, I didn’t want to drop a tooth on the front sprocket, so I upsized the rear to help keep the chain off the swingarm.
Like Gravy said above, if I’m not planning on ripping around at warp speed all the time, low gearing makes it lots more fun. This was partially determined when I decided to see if my S4Rs would actually do the 155 MPH it’s supposed to do. Turns out, I can’t go that fast. I chickened out around 125 or 130 because I physically couldn’t hang on anymore. The wind load on a naked bike at that speed is incredible. Fairings are important. And 100 is plenty fast.
So the front end is basically finished, now I need to figure out how to get 200mm of suspension travel out of the rear. I toyed with the idea of ditching the linkage and using a matching KTM SMR PDS shock, but that was going to be major(er) frame and swingarm surgery. I scoured the Öhlins site for hours, since they have shock stroke and eye to eye data trying to find a factory shock that would give me the right travel and work with the existing linkage. The closest I could find was a Desert Sled shock at 81mm travel and 335mm eye to eye. But it only had an eyelet at one end and a yoke at the other. I needed eyelets on both ends. And it wouldn’t be valved for my application. It was looking like I needed a custom solution. I found a lot of European companies (a couple in Italy, one in Sweden) that could maybe build me a custom shock, but it was $$$ and a serious language barrier problem. Then I found RaceTech in Southern California. They make full custom shocks— any size, any ends, whatever valving I need. Super cool to work with and I didn’t have to learn Italian. And not as expensive as I thought. Still not cheap though. So, before I committed to having a custom shock built, I decided to verify it was going to work at all and I built my very own custom shock out of square tube. #mockshox
![46882E86-5F39-4814-98AF-6508EF31A014.jpeg 46882E86-5F39-4814-98AF-6508EF31A014.jpeg](https://www.rme4x4.com/data/attachments/117/117913-7e497c397af8911d2cc285a74f42f548.jpg)
![1F44EF54-FC31-4678-9A71-FA22FAEB39D5.jpeg 1F44EF54-FC31-4678-9A71-FA22FAEB39D5.jpeg](https://www.rme4x4.com/data/attachments/117/117914-4a712ce24f81d98ab5a6a617f237ba44.jpg)
![224F9672-4D2B-4D07-A20D-A5ECF649AAC6.jpeg 224F9672-4D2B-4D07-A20D-A5ECF649AAC6.jpeg](https://www.rme4x4.com/data/attachments/117/117915-5b83d769d7d39869f6ebf1a033ab0d58.jpg)