Front Suspension

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willywill

Front Suspension

Post by willywill »

I'm curious as to why some folks here poke fun at longer travel forks? I have read a few comments in the past too so I am not just talking about recent ones (nor am I offended or anything either.)

I think I understand that these bikes were designed to be used with 63-80mm forks, not 100-120mm forks. I have heard a few of you mention that the handling will be poor, it won't turn well, and other performance problems due to the geometry being thrown off, larger turning radius, etc.

As some may remember, the first photos I posted of my XX I was sporting a Quadra 21R and a Ringle 0 rise stem. I then put the Manitou Black on with the same stem. This was seriously awkward (as was the original setup but I got used it after a few rides) so I changed to a stem with some rise and some handlebars with rise and the handling issues were solved. I have been riding this setup for a while now and I can't tell that it isn't responsive or suffering from poor handling except the steep in the saddle climbing issues.

Now I admit, it does look a little funny and certainly isn't period correct but since I was going for comfort and performance I feel like I achieved my goals. The old forks I have used are quite lackluster compared to the Black, though they were quite a bit lighter. I have looked at the geometry, turning radius primarily, and I understand the concept of rake and trail from riding motorcycles, which makes sense when operating at high speeds that even a slightly longer arc will have a noticeable effect on handling, but on a bike at relatively slow speeds? I am not convinced it makes any difference.

Enlighten me oh great and wise Cuda heads!

Most importantly though my steed is reliably hauling me to work and home everyd; gotta love commuting! :mrgreen:

neo_pop_71
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Re: Front Suspension

Post by neo_pop_71 »

By no means am I an expert but increasing the rake and changing the angle of your cockpit will certainly affect the handling. I understand your point about slow speed handling vs. high speed but it seems backwards to my thinking... I want the bike to handle best at high speeds. Long travel forks on short travel geometry frames is simply a bad idea in my book. I think the designers figured out this problem, that's why every frame these days is hydroformed with a steep head tube angle and curving top and down tubes. This also adds strength at the headtube. You're asking a lot 15+ year old frame, one with straight butted welds at the head tube, to handle the stress of a long travel fork. The aluminum frames will stress crack first but even the steel frames (especially the light weight steel ones) will pop their welds.

I approach this from a safety standpoint and doing what you've done does not seem to be the best choice, in my opinion, but I am not intended to be personal in any way... I just think it'll be a matter of time before you waste your frame. The 7000 series aluminum frame, like your Dos XX, is not heat treated. That's why they went with the 7000 aluminum, it saved on the production time and cost, but it came at a price as the frames (like the Dos XX, the Manitou frames, the Giant Tomac World XC Chapionship, and many others) develop stress cracks. Check out Mixalive's awesome save on his Dos XX Team bike, it's a killer story with plenty of pics, and he was running a proper travel fork and it still stress cracked!

Granted I tossed out a bit more than my 2 cents, so sorry for goin' on...

-D-

willywill

Re: Front Suspension

Post by willywill »

Neo,

Thanks for all the words of wisdom! I hadn't thought about it from a safety standpoint or from one of damaging the frame, you make some very good points that I will definitely take into consideration, especially since I now have a sweet Mag 21 at the house.

I am familiar with the heat treating process of strengthing Al but I was not aware that was the cause of some of the stress cracks on the frames you mentioned (especially the Manitou frame, I have yet to see one listed on Ebay that doesn't have the crack).

I am still not yet convinced it handles any better or worse (but like always, gotta keep that mind open :D ) but when I get around to switching the fork out I will make sure to do some testing of sorts.

So this will bring me to my next question...if I swap the fork that means I am going to be changing wheels and brakes/levers. I figured I would go with some XT/XTR V-Brakes, but what do you think about for a set of wheels? I am set up to build my own and have laced about a dozen wheels in the past so I would prefer to go ground up. I love the Ringle Hubs but they might be out of my budget (getting ready to move soon). I had a set of XTR hubs a while back and liked those fine. I really have more questions about what kind of rim to get. What was the hot ticket back in those days? Mavic 221?

Thanks again for all the info!

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Mark
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Re: Front Suspension

Post by Mark »

To weigh in on the geometry point, when running with a standard-fit fork on my XXTeam, I could ride slowly, no hands. This is because the tire rode on the sweet spot, where it was meant to.

When I swapped to a longer fork, it pitched the headtube slightly, and the contact patch went back a bit. Now, when going no hands at slow speed, the bars have a tendency to turn left or right, and not stay centred.

Keeping technical terms out of it, the handling is affected. It's whether or not you notice, that makes the most difference.

:)

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vpc66
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Re: Front Suspension

Post by vpc66 »

THANK YOU MARK! As a kid with my bmx bikes I had no problem riding hands free and I do it on my son's bike as well as my road bikes....but I have never been able to do it on the cuda which always got me and my forks just have 80mm travel....I never thought of the little bit more travel giving the problem.
Relax and have deep water thoughts.

F.C.C.R Ride hard,Ride Fast.....Go Insane

willywill

Re: Front Suspension

Post by willywill »

Not to be the devil's advocate...but wouldn't a longer travel fork lengthen the wheelbase and thus make it more stable? I agree with you Mark about it being harder to ride no hands with the longer fork, it definitely seems twitchy and more likely to veer left or right but I would think those would be the attributes of a more nimble ride?

At any rate, I am going to heed Neo's advice and not run the risk of cracking my headtube. If for some reason no one out bids me on the Easton frame (which I admit I increased my max to $420 for anyone who is interested)I will swap those wheels out with mine.

Thanks for all the feedback ya'll!


neo_pop_71
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Re: Front Suspension

Post by neo_pop_71 »

C'mon seller... what the hell?

"Martzocchi"

How can you post an ad on Ebay and get the spelling wrong?

Especially Marzocchi... clearly this seller has never been a fan of Marzocchi's ad campaigns over the years! Let's take a trip to Interbike... they are Italian, so well known for a long history of two-wheeled appreciation. Fabulous displays at their booths every year at Interbike!!!

Enjoy!

-D-

p.s. I love the old man in the picture... he's admiring her eyes :D
Last edited by neo_pop_71 on April 7th, 2012, 12:06 pm, edited 1 time in total.

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vpc66
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Re: Front Suspension

Post by vpc66 »

The sure fire way to get guys to buy something, display BIG gorgeous...........eyes
Relax and have deep water thoughts.

F.C.C.R Ride hard,Ride Fast.....Go Insane

willywill

Re: Front Suspension

Post by willywill »

I just converted to Marzocchi... :o

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