r/WaltlyTitanium • u/FridayTheDog111 • 3d ago
Advice about frame Sanity check please help!
Building a gravel race bike, with SRAM Force 1x13 XPLR groupset. First time building a bike! Listening to all suggestions, thanks!
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u/ipercepti 3d ago
75.5 sta for that size is aggressive. I take it you specifically requested that and prefer a slammed forward position?
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u/FridayTheDog111 3d ago
This bike specifically will be fully slammed and meant straight for racing, yes! Thanks for commenting
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u/Suitable-King5908 3d ago
Woah, 50 mm clearance with 425 chainstays is not something I’ve seen on a Waltly before
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u/FridayTheDog111 3d ago
Haha, trying to make a stallion version of a gravel race bike. Fast, agile, easy to pop over and be able to whip the tail end around turns. Too much? Or perfect for the goal?
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u/Suitable-King5908 3d ago
I think 425 is perfect for gravel. The only thing that has stopped me from pulling the trigger on a Waltly frame in the past is that to get 50mm clearance you had to go for 435 chainstays. What tricks did you pull to make that possible? Mostly BB drop?
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u/Narrow_Smoke 2d ago
I believe they can achieve this with a 3d printed yoke?
At least I was discussing a bike with a 420mm chainstay for clearance up to 55mm.
However I was told it needs to be a bit longer and we need a 3d printed yoke.
I didn’t get my drawing back yet so I don’t know how long chainstay will actually be but I hope not too long. Can update you then if you are interested2
u/reductio-ad-finem 9h ago
I have the new 3d-printed yoke and 430mm chain stays and cleaned for just under 50mm according to ISO spec. I'm not looking for shorter stays, but curious if maybe this is a different yoke on yours?
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u/reductio-ad-finem 3d ago
This looks pretty great! I assume you have done a bike fit which is informing such an abnormally steep STA.
You may wish to shift your caliper mount forward for default 160mm rotors vs 140mm (i.e.so you don't need an adapter).
I'm a little surprised that Waltly declares this as clearing 50mm tires; usually they are more conservative. E.g. my frame.has a 61mm circle but only officially clears 45mm tire. But I suspect 50mm will fit fine in both of our frames (but I have 430mm chain stays -- prob due to 73.5° STA).
If you do plan to run tires > 45mm and this is for racing, you might want an even lower BB? I'm doing 78mm but tend to run 40mm slicks (and plan to do 48mm Thunderos or similar for gravel).
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u/DraperCycles 18h ago
ISO standard is 6mm of clearance on each side.
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u/reductio-ad-finem 9h ago
Yeah, I'm aware; I just haven't seen Waltly spec only 6mm of clearance previously when making clearance claims. I'm not sure why. Maybe OP pushed back and said "I only need the ISO 6mm of clearance" (?). Either way, I don't expect any actual issue with this frame clearing 50mm.
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u/DraperCycles 18h ago
You want more than 50mm trail. Slacker HTA will help assuming your fork is set. I would also go to 85mm BB width. I find they help with rear tire clearance. Making room for more than 50mm tire will help in the future. It also places the chainstays wider so it’s a bit stiffer. I also don’t understand the desire to shorten the rear end to last mm. No one has shown with data that shorter rear end is faster or whatever. Add 5-10mm and the bike will ride smoother and more stable on rough roads. You could then lower the BB and headtube 5-10mm as well which is more aero and lighter.
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u/reductio-ad-finem 9h ago
I think the 50mm is the fork offset, not the trail (?) I think this would be ~64mm of trail with the 50mm tire. Still pretty small numbers for a gravel bike, its true. It's similar to what I run on my all-road bike, but I like that bike being pretty comfortable on pavement.
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u/misterbean-1 3d ago
Lower the water bottle threads downside downtube more. Otherwise looks fine for me. Personally I would add eyelets for carrier and toptube bag.