Mountain Biking - 20" + MTB frames?

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phantomcow2
11-27-04, 01:31 PM
Im just wondering, it seems to me that many of the mountain bike frames out there are not often larger than 20". Why is that? Is a 21" frame for a mountain bike ridiculous?
Maelstrom
11-27-04, 01:57 PM
21" mtbike woud be perfect for someone 6'8 ish on trails. Its ridiculous because on a mountain bike you need room to move. Typically even xc guys have a smaller fitting bike than a roadie would for a road bike.
swifferman
11-27-04, 03:06 PM
How tall are you phantom cow?
So Shaq and Yao Ming would need 24" than eh...
LOL
Juniper
11-27-04, 03:39 PM
So Shaq and Yao Ming would need 24" than eh...
LOL
Or, a seatpost as long as a broom stick and a stem the size of a loaf of french bread! :D
VosBike
11-27-04, 04:04 PM
I ride a 21 inch frame
biggest mistake ever, im 6'3'' and usualy ride somewhat melow XC, and even then its a bit too big, although i love when we get off the technical stuff and i can actualy get a full pedal stroke, better than my 18'' commuter bike at least
phantomcow2
11-27-04, 04:22 PM
well thats the thing see, I will also be using htis for like 70% road, with decent length commutes, about 10miles/day and that isnt including joy rides.
Maelstrom
11-27-04, 04:28 PM
Well here is the simple answer...
there is no perfect bike for what you are looking for. You can't have optimal road type pedalling/body position and a safe maneuverable trail bike. You can have a great road type pedaller that will feel big and unstable on trails or a trail bike that will be a little slower and not maximize power output on the road.
phantomcow2
11-27-04, 04:38 PM
Yea Maelstrom i was coming to that conclusion, well i went for the 21 inch. I suppose when im on the trail i can lower hte seatpost quite a bit.
Maelstrom
11-27-04, 04:41 PM
It will likely still work, depending on how tech the trails are. You may not notice.
phantomcow2
11-27-04, 05:23 PM
Yea i was thinking it would work just fine. I mean a 21 inch frame both my feet can touch the floor flat footed, or just about. The offroad that i do is mostly hilish trail with many roots (NH) and rocks.
djcolorado
11-27-04, 08:21 PM
I am 6'2" and have a 34" inseam and wear 36" length sleeves so it takes a pretty big frame to not feel cramped up. The frame style makes a big difference on how manuverable the bike feels though. I have a 21" GT Avalanche that is about seven years old and just bought a 21" Rockhopper Comp. The Rockhopper feels much more manuverable. I think part of the reason is that the top tube slopes down a lot more which lowers the center of gravity and makes the frame more compact for less inertia.
Juniper
11-27-04, 09:13 PM
I am 6'2" and have a 34" inseam and wear 36" length sleeves so it takes a pretty big frame to not feel cramped up. The frame style makes a big difference on how manuverable the bike feels though. I have a 21" GT Avalanche that is about seven years old and just bought a 21" Rockhopper Comp. The Rockhopper feels much more manuverable. I think part of the reason is that the top tube slopes down a lot more which lowers the center of gravity and makes the frame more compact for less inertia.
Yup!, the whole design of frames has changed over the years. I used to ride a 19.5" when the top tube was basically parallel to the ground. Now I ride a 17" and could do fine on a 16".
Giant makes (and we occasionally sell) a 25" frame. I can't even really test ride the thing. My boss is 6'4 and its uncomfortable for him.
cryogenic
11-27-04, 10:17 PM
That's HUGE. I have noticed that mtb'ers do tend to ride smaller frames than they would ride if they were buying a road bike.
stapfam
11-28-04, 01:13 AM
Giant makes (and we occasionally sell) a 25" frame. I can't even really test ride the thing. My boss is 6'4 and its uncomfortable for him.
My riding partner is 6'9, 230 lbs, inside leg of the tallest Supermodels you see, and rides a Giant 23" frame. We did try him on a 21" but it was too short in the cockpit. Incidentally, he still has 6" of seat post showing.
When you are this tall and this heavy, one of the advantages of a large frame is the strength that is built into the frame. Giant realise this, and the frame is superb, so why the hell don't the manufacturers realise that Big frame = Big bloke which often means excessive weight. A 230lb rider is going to knock out standard wheels, bottom brackets, chains and anything else that cannot take the punishment of even a gentle ride over the hills. (Kona does with the hoss)
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