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I think this will mostly end up a 'photo dump' and a place for me to scribble down some stuff I'd otherwise forget, but a small intro...
This will be the 3rd frame I've built of this style. The first two were 26", one from cheap ERW (gave the bike to a mate and it's still going!) and the second TIG Brazed in Columbus (also still going): Steel Singlespeeder Home Build
V3 (below) will be 853 / Columbus mix and 29". I'd always thought 26" wasn't dead until I rode a mate's 29er down a known bit of techy trail and it absolutely blew me away. It definitely seems to be more about geo and parts selection than wheel size - except when it comes to rolling over lumpy stuff!
Anyway. I spent a while nerding out with BikeCAD (huge thanks to Brent for the great price on a 'diy-er deal' for the Pro edition) and some geo charts of other bikes I'd ridden and liked, came up with the following:
The plan is to end up with something very all-round-y - a quick blast up the woods with mates, an all day epic or even some short course XC racing / endurance racing. I have a SID fork I can swap out which slackens the static angles by about a degree, but I've built the bike around rigid forks as I love the direct feel (and low maintenance!) of a very simple bike.
I have ridden trials for about 25 years so wanted shortish stays, low standover and a huge dropper to get the saddle right out of the way. The dropouts have 9.5mm of movement which is enough to account for one chain link difference in chainstay length (eg. I plan to run 32:20 as it's hilly round here, but the frame should also take 30:20 for a lighter gear ratio, and 32:18 for a harder one, both with a 6.35mm / 1/4" increase in chainstay length). The rest of the adjustment is to allow for chain stretch. I just hope I can manufacture it accurately enough!
I am also a previously-recovered self-confessed weight weenie in relapse (and proud, ha). Interestingly I find reduced weight - especially on a rigid bike - helps more downhill than uphill. The bike really loves to skip around and get out of the way of bumps, sure it can get a bit lively but if you let the bike go on its merry way it's a lot of fun.
Parts-wise I've gone fairly pimp, so given a projected ~2kg / 4.4lbs frame weight it should be a smidge over 9.2kg / 20lbs with the SID fork (750g / 1.6lbs less rigid). I know that frame weight sounds very light but, as the previous frame, I have worked hard on reducing the bulk of 'lumpy bits' like BB shell, dropouts, etc - they hide SO much weight, especially in steel frames. I'm also not a heavy rider and don't really 'send' stuff, so I can get away with light bikes.
I'm not trained in any of this, but been in the bike industry over 20 years now and love sticking lumps of metal and plastic together in odd ways with various amounts of wheels hanging off the bottom. Such as...
And...
Oh yeah, working title is the ARSE 29er. Adam R Singlespeed Experiment: 29er.
So there we have it. Intro done. Tips from more seasoned frame-builders, questions, or anything else along the way are always welcome!
This will be the 3rd frame I've built of this style. The first two were 26", one from cheap ERW (gave the bike to a mate and it's still going!) and the second TIG Brazed in Columbus (also still going): Steel Singlespeeder Home Build
V3 (below) will be 853 / Columbus mix and 29". I'd always thought 26" wasn't dead until I rode a mate's 29er down a known bit of techy trail and it absolutely blew me away. It definitely seems to be more about geo and parts selection than wheel size - except when it comes to rolling over lumpy stuff!
Anyway. I spent a while nerding out with BikeCAD (huge thanks to Brent for the great price on a 'diy-er deal' for the Pro edition) and some geo charts of other bikes I'd ridden and liked, came up with the following:
The plan is to end up with something very all-round-y - a quick blast up the woods with mates, an all day epic or even some short course XC racing / endurance racing. I have a SID fork I can swap out which slackens the static angles by about a degree, but I've built the bike around rigid forks as I love the direct feel (and low maintenance!) of a very simple bike.
I have ridden trials for about 25 years so wanted shortish stays, low standover and a huge dropper to get the saddle right out of the way. The dropouts have 9.5mm of movement which is enough to account for one chain link difference in chainstay length (eg. I plan to run 32:20 as it's hilly round here, but the frame should also take 30:20 for a lighter gear ratio, and 32:18 for a harder one, both with a 6.35mm / 1/4" increase in chainstay length). The rest of the adjustment is to allow for chain stretch. I just hope I can manufacture it accurately enough!
I am also a previously-recovered self-confessed weight weenie in relapse (and proud, ha). Interestingly I find reduced weight - especially on a rigid bike - helps more downhill than uphill. The bike really loves to skip around and get out of the way of bumps, sure it can get a bit lively but if you let the bike go on its merry way it's a lot of fun.
Parts-wise I've gone fairly pimp, so given a projected ~2kg / 4.4lbs frame weight it should be a smidge over 9.2kg / 20lbs with the SID fork (750g / 1.6lbs less rigid). I know that frame weight sounds very light but, as the previous frame, I have worked hard on reducing the bulk of 'lumpy bits' like BB shell, dropouts, etc - they hide SO much weight, especially in steel frames. I'm also not a heavy rider and don't really 'send' stuff, so I can get away with light bikes.
I'm not trained in any of this, but been in the bike industry over 20 years now and love sticking lumps of metal and plastic together in odd ways with various amounts of wheels hanging off the bottom. Such as...
And...
Oh yeah, working title is the ARSE 29er. Adam R Singlespeed Experiment: 29er.
So there we have it. Intro done. Tips from more seasoned frame-builders, questions, or anything else along the way are always welcome!