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Discussion Starter · #1 ·
I've read a lot about the new suspension fork offsets,44 to 46mm, 52mm,etc, has anyone changed their fork from the old to the new? If so, how did it effect your bike's handling? I'm not so curious about a change to G2, but would still be interested. What bike, size,crank length, stem, bar, anything that might effect handling and how do you feel about the change.
 

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Not sure someone will feel pressed to write a general essay in this very thread on all the variables at work, based on you original post without any specifics on your bike, type of riding, or your own former experiences and preferences.
 

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Cloxxki said:
Not sure someone will feel pressed to write a general essay in this very thread on all the variables at work, based on you original post without any specifics on your bike, type of riding, or your own former experiences and preferences.
That's OK, many people don't want to read about all of the variables at work, they just wanna know how it feels (thread originator included, apparently).

Having said that:

I have tried both a Fox F29 at 80 and 100mm at 44mm offset and an "older" Reba (2007) with the 38mm offset on two different frames.

Frame #1 is the Intense Spider 29, which by all accounts has the old school 29'er geometry and a fairly ridiculous 73deg head angle that I'd imagine was designed around the Reba. I happen to love how quickly the frame handles and never fell victim to O.T.B. adventures like others have claimed. The Reba at 80mm was ultra-quick, maybe a little too much so. At 100mm it's friggin' PRECISE, and I like it a lot. To borrow a term from GuitarTed's arsenal, this is a 'steer from the hips' type of single-track weapon, and I feel like I've definitely figured out how to make it work for me. The Fox at 100mm on there was actually not a dramatic difference. It felt like the front wheel was sort of 'out there' for sure, so much so that when going back to the Reba it seemed almost beneath me. I don't really know which one I like better, they both felt good to me, yet different, but the Fox is certainly stiffer in every way (flex, fork action, etc.) than the Reba. I am an adaptable kind of guy and unless a change I make is just wayyy off, I can get used to it in a few miles. The reason the Fox is no longer on there is because....

Frame #2, my Soul Cycles Dillinger built up singlespeed was complete shite with the reba on it, and I could not adapt. A 'floppy' steering feel made it fairly hard to ride with the Reba, so I put the Fox on there and now it's *almost* perfect. So close that bar and stem combos really make a big difference now in how it feels (i.e. riser stems sort of bring it back to floppy, whereas flat ones [or, negative rise, if you prefer] tend to open up the sweet spot in the steering quite a lot). I spoke with the guys at Soul and they said they developed it with a Manitou Minute, but weren't clear what the offset was (I think the 100mm is at 44mm, so same as the Fox). So, the Fox stays on the Dill and the Reba on the Spider.

Conclusion? Um, not sure there is one, but based on my limited experience it seems that "old school" geometries are more compatible with "new school" offsets than new school geometries are compatible with old school offsets.
 

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Discussion Starter · #8 ·
That's what I'm talking about.
Kardy, so the steep head angle of the Spider feels better with the shorter offset of the Reba, longer WB and more trail, but the Dillinger feels better with the Fox, What's the head tube angle of the Dillinger? I would guess slacker, which brings me to RockStarRacing and your G2 Paragon. I thought the G2 Fisher's had a slack HTA, like 69.5, so with the 52mm G2offset the WB shortened and the steering quickened. It sounds like you are having the opposite experience, What fork are you considering?
 

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I believe the Dill is at 71.5, but I can't get their website to come up on my browser at the moment to confirm that. May even be 70.5. Try ridesoul.com...

I agree with Rockstar on the G2 bikes that I've ridden - on my local trails they are like driving a boat with a broken rudder - they simply won't turn. I bet they're killer on long fast (and straight) descents though. But I digress...
 

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Maheoway said:
That's what I'm talking about.
Kardy, so the steep head angle of the Spider feels better with the shorter offset of the Reba, longer WB and more trail, but the Dillinger feels better with the Fox, What's the head tube angle of the Dillinger? I would guess slacker, which brings me to RockStarRacing and your G2 Paragon. I thought the G2 Fisher's had a slack HTA, like 69.5, so with the 52mm G2offset the WB shortened and the steering quickened. It sounds like you are having the opposite experience, What fork are you considering?
Just a note- comparing steeper head-angle bikes with less offset to slacker head-angle bikes with more offset... BOTH the slacker head angle and greater offset of the "newer" geometry INCREASE the wheelbase. Trail general balances out at about the same, but flop factor is greater. So, it could be that people who don't like the G2 geometry and say it won't steer around corners are either noticing the extra wheel flop or (more likely) they are noticing the longer wheelbase (OK, longer front-center, but longer fc= longer wb if chainstay length is kept the same).

My bike has 72.5 degree head angle and 39mm offset; I haven't ridden any different 29er geometries, so I can't help with tales of actual riding experience...
 

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Discussion Starter · #11 ·
RockStarRacing said:
i bought a 29er paragon with G2, for me, i didnt like it, worst 29er ive ever ridden. couldnt get it round corners. but this is my opinion, you may like it. G2 F29 for sale here if you want to try it......
What about your stem length and height and handlebar height? Kardy addressed the same thing on his Dillinger. My Pivot 429 with the Fox at about 44/46mm offset was so quick, opposite your problem, that I had no confidence in the front end, I couldn't plant it. For reasons not applicable, I use a high bar, a stem 90mm long and 10 degree rise and had about 32mm of spacers under the stem, by lowering the stem 18mm I found I had much better control of the bike. I weighted the front end, you might try shortening your cockpit to unweight the front end.
Anyone else?
 

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Discussion Starter · #12 ·
John_Biker said:
Just a note- comparing steeper head-angle bikes with less offset to slacker head-angle bikes with more offset... BOTH the slacker head angle and greater offset of the "newer" geometry INCREASE the wheelbase. Trail general balances out at about the same, but flop factor is greater. So, it could be that people who don't like the G2 geometry and say it won't steer around corners are either noticing the extra wheel flop or (more likely) they are noticing the longer wheelbase (OK, longer front-center, but longer fc= longer wb if chainstay length is kept the same).

My bike has 72.5 degree head angle and 39mm offset; I haven't ridden any different 29er geometries, so I can't help with tales of actual riding experience...
There's always something new to learn, what's wheel flop?
I've read a lot about offset, rake and trail, in my mind increasing the offset, from 38mm to 44mm, would lengthen the WB, that is not the case, the WB is shortened and the trail is decreased, quickening the steering. of course there are other variables like cockpit, CSTY length. which on any given bike is a relative constant, fork length, 80 to 100 and up, tire size and inflation, which will also effect handling.
 

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Maheoway said:
There's always something new to learn, what's wheel flop?
I've read a lot about offset, rake and trail, in my mind increasing the offset, from 38mm to 44mm, would lengthen the WB, that is not the case, the WB is shortened and the trail is decreased, quickening the steering. of course there are other variables like cockpit, CSTY length. which on any given bike is a relative constant, fork length, 80 to 100 and up, tire size and inflation, which will also effect handling.
Actually, your intuition is correct, increasing the offset increases wheelbase AND decreases trail. Check out the diagram:

http://www.phred.org/~josh/bike/trail.html

Wheel flop is the number of millimeters the bike falls when you turn the bars from straight to hard left or right.

http://www.kreuzotter.de/english/elenk.htm

see also:
http://tinyurl.com/7g7fqp

One more thing to keep in mind- trail will differ between a given bike with a 100mm travel fork and a 80mm travel fork of similar offset. The longer crown-axle on the longer-travel fork slackens the bikes head angle, and increases trail.
 

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Discussion Starter · #14 ·
John_Biker said:
Actually, your intuition is correct, increasing the offset increases wheelbase AND decreases trail. Check out the diagram:

http://www.phred.org/~josh/bike/trail.html

Wheel flop is the number of millimeters the bike falls when you turn the bars from straight to hard left or right.

http://www.kreuzotter.de/english/elenk.htm

see also:
http://tinyurl.com/7g7fqp

One more thing to keep in mind- trail will differ between a given bike with a 100mm travel fork and a 80mm travel fork of similar offset. The longer crown-axle on the longer-travel fork slackens the bikes head angle, and increases trail.
I looked at the diagram. "Offset is the forward displacement of the wheel axle in relation to the steering axis." Looks like the wheel base is shortened, to me.
 

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Maheoway said:
I looked at the diagram. "Offset is the forward displacement of the wheel axle in relation to the steering axis." Looks like the wheel base is shortened, to me.
In the diagram, you'll notice the long red line- that's the steering axis. Offset (also called rake) moves the front wheel forward, and forward being farther from the rear axle (note where the shorter red line is, and how it runs through the front hub), makes the wheelbase longer.
 

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The new fork offsets WOULD quicken your steering if your bike came with a 38mm offset fork because it decreases fork trail.
The G2 bikes don't steer any quicker than old school 29ers. The fork offset was INCREASED BUT the head tube angles were DECREASED so that the fork trail remained the same. (The Hi Fi is an exception.)
You might like less fork trail or it might screw you up, there's a risk.
 

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Discussion Starter · #18 ·
John_Biker said:
In the diagram, you'll notice the long red line- that's the steering axis. Offset (also called rake) moves the front wheel forward, and forward being farther from the rear axle (note where the shorter red line is, and how it runs through the front hub), makes the wheelbase longer.
I thought wheelbase was contact patch to contact patch, your saying it's axle to axle. Interesting
 

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Discussion Starter · #19 ·
John_Biker said:
In the diagram, you'll notice the long red line- that's the steering axis. Offset (also called rake) moves the front wheel forward, and forward being farther from the rear axle (note where the shorter red line is, and how it runs through the front hub), makes the wheelbase longer.
According to Sheldon Brown's glossary, wheelbase "in general is center of wheel to center of wheel" according to Wikipedia "or contact patch to contact patch." Obviously, given geometry, these are not the same and make a big difference in a discussion like this.
John, this is interesting.
 

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I went from Reba to Minute.
Minute steers more quickly.
It also deflects easier and isn't as stable- harder to ride no-hands.
So far, I'm leaning towards the steering difference being more of a pro than the cons of stability and easier deflection, but the verdict is still out.
That's my real world tale, I guess.
 
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