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Fast99
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Discussion Starter · #1 ·
Hi, guys i recently bought an intense 5.5 in a size small and had a hellava bother with my forks hitting the downtube of my shiny new frame. I was wondering what the solutions are (i am running Pikes 454 although i also have a set of 2007 fox floats which i could use). Do any of you own a small size frame and what forks are you running?
Cheers.
 

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Fast99
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Discussion Starter · #3 ·
Cheers, it looks like I will have to buy a King headset and a larger crown race. I just bought a new Raceface one as well, ahh well such is life.
 

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I have a 4mm Ventana crown on my medium 5.5, no effect on handling. It just looks a bit strange at first and you might have some people on the trail tell you your fork was not installed properly ;)
 

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Fast99
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Discussion Starter · #5 ·
Hi, i have bodged a solution. I fitted a 5mm spacer under the crown race (the crown race is still nice and tight on the steerer) which meant that the forks (fox floats) nearly cleared the frame. I then had to file a 1mm or so of the blue and red adjustors on top of the forks and hey presto it clears. I have coloured in the adjustors with coloured markers and you cannot even notice that they have been filed down. A bit of a bodge but i didn't want to buy another headset as the one that i have is nearly new and the Ventana crown race is hard to get in the UK.
 

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I don't understand why Intense doesn't address this issue. It's been known for at least a couple years.

Whazup with that?
 

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Interesting thought. It hadn't occured to me to look at it that way.

I can't recall seeing any complaints about this issue on other popular frame/fork combos though.

It just seems strange to me that they (Intense) would not seek to design the frame so it would accomodate the most universally desired forks of the target customers.

It is almost incomprehensable to me that they don't at least offer an optional fix to those customers who run into this instead of forcing them to do all of these aftermarket adaptations I've read about.

Weird.

Is there anywhere that the forks that do and don't work are listed all in one spot? I'd be a tad miffed if I bought an expensive frame and apparently compatible fork only to find out there were interference problems and I had to do some sort of work around.

Has Intense posted any warnings about this or do they just let folks get burned?
 

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Unfit Norwegian
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It seems that Intense has been cooperating with manitou quite a lot, and manitou forks seem to fit without problems. Whatever one might read into that.

And I guess using a bent downtube to clear tall fork knobs has drawbacks too.
 

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Fast99
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Discussion Starter · #12 ·
meat tooth paste said:
Do you have photos of this solution. Would be curious to see.
Hi here are a couple of pics, sorry about the quality but I took them with my phone. I also have to say that I think Intense should solve this fork frame problem as until i built mine up i was completely unaware of this problem. As I had already bought a Raceface headset I certiantly wasn't keen on spending another £100 on a King one and a Ventana crownrace.
 

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Now I'm really curious about this.

I've mostly been a roadie over the years, so my experience with mountain bikes is limited, though I am now more into trail riding for fun and fitness.

How serious is this problem for the average rider?

What other popular bikes have this issue?

How far do you have to be turning your bars to run into the interference? Is the average rider affected, or just those creatures who turn their bars all the way to the side as they fly though the air like maniacs (wish I could do that)?

Is the damage caused just cosmetic, or is there a danger of causing costly damage to the fork or frame?
 

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Intense is not the only frame manufacturer to have this problem. Why do you think that Ventana are making their 4 and 7mm. crown races? I forget which other brands have the same issue but I remember a discussion quite some time ago. I got my 5point5 in the beginning of 2004 and knew about it then. Personally I think the fork manufacturers started out with a profile for the crowns and then as they felt the market was demanding more features they added adjustment knobs on top of the crown. Some of them have quite high profiles and they get higher as knobs are turned out. Also look at the shape of the crown on a Fox fork. The ends where the stanchions fit into the crown turn up even without the knobs, whereas Manitou's crown slopes down. That is why Manitou forks have no problem.

Twister, it is not that you are likely to hit the down tube while riding but if you crash and your front end is turned all the way or even when you carry the bike, the knobs can hit the down tube hard. In some cases there is no way the knobs will pass and will likely damage the frame and/or fork. In others it just scratches the paint. Either way I would not be happy.

Ronnie.
 

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Actually the reason Manitou are able to go with this unique sloping crown design is due to the fork legs/chambers running past the axle points, allowing for them to lower the entire fork quite considerably. This is a design unique to the Manitou's (of all the main market leaders) and is also the reason they have much lower axle-to-crown heights when compared to their more traditional rivals R.S., Marz & Fox.

Also, the Fox crown actually level's out as opposed to turning upward, but regardless with the large knobs they love using they are always going to cause possible clashes with smaller frames downtubes. Rockshox aren't much better at this stage either.

The main solution to the problem? Either shrink all the mechanics required at the top of the stantions (could be expensive) or simply copy Manitou...which isn't going to happen (overnight at least). I have a feeling they will faze in a similar design to the Manitou's over time so no one notices the similarities... ;)
 

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Thank you, Ronnie and Starship, for making this issue an understandable one for me.

I'll spend a little time later on looking at some web sites and further educating myself with a search or two.

Other than forming a bend in the top/front of the down tube are there any other frame oriented fixes for this?

How does the Ventana crown race fix work?
 

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Twister said:
How does the Ventana crown race fix work?
Ventana make two crown races, 4mm. and 7mm. thick which you use instead of the standard crown race that comes with your headset, to move the fork crown away from the frame. They are however made only for Chris King headsets. I personally don't think it looks very nice but it does the job. Here is a picture of the 7mm.

Ronnie.
 

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I have a 4mm Ventana crown race under a Chris King w/ a Fox Talas RLC. No handling issues and no fork downtube contact.
 

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OK. The crown race replaces the standard race at the bottom of the headtube, which in essence, pushes the fork down 4 or 7 mm from the normal position allowing the fork to clear the down tube.

This has the side effect of raising the front end an equivalent amount, which causes a very slight geometry change (too small to matter probably, but I'm trying for understanding).

Am I on the right track here?

If Intense slightly extended the head tube on the bottom would this have the same effect?

Why don't the headset manufacturers get in the game and make headsets that incorporate a modification to address this? Seems like it would be easy enough, and would be a way to sell headsets to those who have this problem. They might be able to make things look a little nicer and more integrated too.
 

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Twister said:
...Why don't the headset manufacturers get in the game and make headsets that incorporate a modification to address this? Seems like it would be easy enough, and would be a way to sell headsets to those who have this problem. They might be able to make things look a little nicer and more integrated too.
Actually FSA do offer a larger bottom stack for one of their headsets (this is the lower part of your headset, where the bottom bearings are housed that rest on the top of the fork, similar to the top). Can't remember the model but they offered two options apon purchase - standard or large lower stack height.

One problem is all headsets have different 'stack heights' (the height of the top and bottom portions that pretrude from your frames headtube). Its more often than not quoted as part of the spec of a headset as (like you've found out) it can be an important consideration when building a bike's front end. I myself overcame a minor downtube clash with my forks by using one of the larger headsets on the market, the FSA Pig DH Pro. If i had used a Chris King i would have also required a 4mm Ventana spacer.

Anyway I think the solution of shaving a little off the knobs is the most economical at this point as it doesn't require you to outlay for a new headset & spacer nor does it effect the stock geometry (unless you want to). ...if you don't like that idea its Chri$ King & Ventana time... :rolleyes:

:thumbsup:
 
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