Hi got a Boardman team frames with 120mm rear travel bike came with 130mm travel rock shock fork fitted, I want to put a pair of marzocchi triple crown drop offs on it, I’m goin to shorten the travel to just 140mm but here’s the biggie will the frame be fine with triple crown forks on even though when I bought it it had single crowns on (i’m assuming the frame was designed for single crowns)

Why?

*SHAKES HEAD*

*SHAKES HEAD*

I wouldn’t do it, not because the frame won’t take it, but for a whole number of other reasons – weight, aesthetics, flexibiity, performance etc.

Hello 2001

Boardman frames are very flexy so it would probably snap with those forks. Its a lightweight xc frame…

Daveyboy the rock shoc that are on it are ruined And I have The marzocchi forks in the garage and I’ve always liked the triple crown look, so thought I may aswel save on buyin new forks.

Scunny as for your lovely sarcy comment I’ll refer to an old saying “if it works why change it” after all the bike only gets used in this country it’s doesn’t really need a grands worth of forks putting on it…So why not just use what’s hanging around…

Thanks mjsmke thought that would be the case

nah its a bit wrong that
lightweight frame with big old forks
will they even fit thought boardmans were tapered head tubes

Sell the downhill fork and buy a single crown one?

So why not just use what’s hanging around…

Because they would not work so well with your (lightweight / XC / not designed for those forks) frame.
You really would do better to use some second hand forks or look at ‘budget’ (although seem surprisingly good these days) forks.

Unless you want aesthetics of triple crown forks – in which case do it and don’t ask people on STW for an opinion.

aye go on, come back and tell us how it rides.

Rob – hadn’t even bothers to check that yet
Davey – I was trying to avoid having to look for new forks but looks like I’ll have to now, any suggestions?
Matt – I thought it was best to get a second opinion on whether or not I would snap the frame and get a mouthful of dirt, I like my teeth how they are lol

Merlin cycles often has some very good online deals for single crown forks. .

Thanks mike just having a nose on chain reaction, I’ll have a poke around on there too

You don’t have to get new forks. But the general feeling is that it’d be wrong!

Even something like some relatively cheap Toras etc would be better than a set of old, heavy triple clamps?

Why would you put any more stress on the frame unless you were going to ride the bike harder / over bigger drops once the fork has been sortened to suit?

Same forces acting at the axle = same forces acting at the steering head no mater if its a triple crown or not.

It will be heavy

What’s the point of putting DH forks on it and then dropping the travel? You’ll get all of the disadvantages (heavy, crap lock, potential to damage the frame) without the benefit of a bucketload of travel. You’d be better off flogging/swapping them for something single crown.

Edit – The potential for frame damage is from the tops of the stanchions smacking the frame in a crash, since the frame definitely won’t have been designed with that type of impact in mind.

Same forces acting at the axle = same forces acting at the steering head no mater if its a triple crown or not.

Not sure I agree – the amount of flex in most forks must reduce ‘shock’ and maximum stress….? (No engineer BTW, just in case I was dazzliung you all with my technical prowess…)

Single crown forks have more flex than tripples so there is less stress on the frame with a single crown fork.

Why would you put any more stress on the frame unless you were going to ride the bike harder / over bigger drops once the fork has been sortened to suit?

Same forces acting at the axle = same forces acting at the steering head no mater if its a triple crown or not.

Well depends on axle-crown length doesn’t it what with moment = force x distance. Also stiffer forks will put a higher impulse through the headtube (this may be counter acted by softer/plusher forks) so higher peak force.

Not buying that making any significant difference. the load has to go somewhere it cannot just disappear. Ok if it flexes the shock loading may be reduced but even so I simply do not buy it making a significant difference

Wibble – if they are longer yes – but the OP was intending to reduce the travel

Best troll for a while…

The mojority of frame stress caused my a single crown fork is towards the bottom of the steerer. however, on a tripple crown you have opposite forces at the top and bottom of the steerer tube. imagine the side view of a bike then push the bottom of the forks backwards. the top of the steerer has forward forces while the bottom has the opposite with trpple crowns.

plus single crown fork steeres have been known to bend during crashes while i tripple wont… where do you think the forces go then?

Its a times like this, the Evil is called for:

mjsmke

With a single crown you get exactly the same push and pull on the top and bottom of the steerer. think about it

Flex would reduce the peak force in Am impact.

I would think that the biggest difference between triple and single crowns is that in a crash a single crown will bend at the steerer tube and with triple crowns the head tube of the frame would take more stress and stop the steerer tube bending but possibly damage the frame instead?

TJ. The flex on single crowns greatly reduses harsh impact on frames. i do agree with you that for unaggressive riding there is no difference but on a rocky trail there is. some frame manufactures use to specify if the warrenty is void with a tripple crown fork. but this was a few years ago when i was in the trade.

Sounds a giggle. Will look a bonkers but you should see some of the homebrew bikes folks on this forum ride. The worst is that you hate it and sell the fork to fund a single crown. Do it.