Let's offroad / mountain bike / mtb / ride dirt

Speak out. I know nothing

Sam just build this as a prototype to test out BTR like geometry

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Aww yisss

Edit - beaten to it

Depends on your intended fork travel and use, innit. Static 67-68 deg with a 120mm fork and effective seat angle from 70-74 as per preference would be great for pedally, cross country, bikepacking stuff I'd imagine. Longer travel forks and winch and plummet type riding suits slacker 65ish head angles, and steep seat tubes to keep you over the front while climbing. All personal taste really.

Only thing I'll say is 420 seems like a very short reach number. My 18" Kona Explosif was 424. My PP Oka is around 450, lot of XLs closer to 470, keeping a stem length under 70mm I will begrudgingly admit is actually quite nice.

@BareNecessities is the tallperson adventuregnar 29er geometry expert, obvs.

65 is Trail centre, probably need an uplift type rigs.

Great for going down stuff. Everything else not so much.

Proportionally my inseam is a lot longer than my reach. It is the same on most of my bikes and is the reason I started making bikes tbh.
I am not cutting any tubes just yet so will consider a longer top tube.

So in other words my proposed geometry is not completely idiotic?
For bike packing and Epping type fun

At a glance, assuming a 120mm travel fork I thought looked sensible as a go anywhere thing.

Same here ish, 183cm with 88cm inseam or so. Hence the Vaya is so short.

I am 190cm and +100cm inseam. My road and cx bike measure 103cm from top saddle to pedal.

@Howard yes 120mm travel.

Quite the opposite here. Long torso and short legs for my height. I've found my old school 71 degree head angle ideal for rigid, but would prefer 69 degrees for a 100mm fork. So probably 68 for 120mm or 67 for 140mm.

That's proportionally very similar to me (~95cm saddle to pedal) and I'm v comfy on the Oka with with 60mm stem and 760mm bars.

Welcome to have a go on it sometime. Riding the stupid things is the only way to find out what works for you, unfortunately

Yeah man. Love to! Thanks

here's my Cotic Solaris 29er geo, I find it quite perfect for bikepacking and Epping fun - done a lot of both, and this bike is the best for a balance between the two.

my singular was better for long flat bikepacking rides but far too squirrely when things got fun and jumpy, due to the HT steepness amongst other things

edit - I see it's 68º HT at 120 travel, exactly as @BareNecessities recommended!

bit slacker than 68, as that's with 2o% sag

oh, yes, can you tell I know nothing about geo?

Haha, doesn't help that there's no standard method of reporting it and half the manufacturers don't state what sag or a-c measurement the charts are shown at. Sagged is definitely more useful for comparing how bikes of differing travel ride.

Sounds like the thread hive mind is in a good place for this question: if I'm replacing a 120mm 26" sus fork with a rigid one, which a-c would be about right, 445 or 465mm?

Edit: NM, got the 465 one. Seems like a 120mm 26" sus fork is around 490 a-c which translates to a 460-470 rigid fork. According to interwebz so must be true.

You guys know about offset headsets right? You can reduce the head angle by 2° or so provided they fit in your frame. I can't be bothered to do the maths but with a longer A-C there might be no effect on the BB height ie. height to bottom of head tube with 120mm fork and 2° offset is same height as rigid fork with no offset.

Useful if you've got an old frame that is otherwise fine but needs a bit of an update at the front end. Obviously it's better to have the right bike in the first place... but if you have to make do

You guys know about offset headsets right?

Nope, never heard of it before but cool idea.

https://www.superstarcomponents.com/en/slackerizer-angle-headset.htm

You guys know about offset headsets right?

Yeah, but

"71 degree head angle ideal for rigid"

I just decidied not to bother using suspension on that bike :-)

After the marin pine mountain dissapointment and then narrowly missing out on a ritchey commando on ebay last week, I am in negotioations with the seller of this thing:

It's a Deng Fu FM190 with 27.5 wheels, cheap and pretty much ticks all the boxes but there's always a catch...

I've asked for detailed pics and how deep it is.

Not worried about the groove, but curious to the use of the Avid caliper washers in that location ?

Caliper bolts too long, just packing them out ?

Maybe the guy couldn't refuse a bit of bodgery when building it up? Am now reading up on fat bike crank q-factors and rear hub widths and chainlines. Is there no end to the number of "standards" around?!

If you're a tall fellow, don't you want a 29er?