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Discussion Starter · #1 ·
Even though I am loving this bike, I am endoing more than I can believe. With the 68.8 degree head angle and a 500mm A-C fork length, it's really too sharp even for me. My ASR-SL wasn't this sharp and the 575 was a slack 71 degrees. Anyway, I need to slacken it up a bit and give up a little of the razor sharp turning so I can keep my bones intact. I'm riding a Large with a 100mm stem and I'm 6 ft tall.

The Gravity Dropper will not fix the issue- my favorite trail has a surprising amount of rocky dips and slow technical sections where I ride with a high seat height or my knees bother me after a while- some of the hits are too quick to keep messing with my seat height. I'm thinking that a fork with a slightly longer A-C length will slacken the head-tube angle a bit. 70 degrees will be perfect. My current Revelation has a 500mm A-C height, the bike was designed for a 505mm but I'm thinking that a 515-520 may get me where I need to be. A QR fork is preferable so I don't have to build a new wheel.

I already have 1.5" of spacers under the headtube. I think a longer A-C fork should do the trick. What do you guys think? Any fork or other recommendations. I need to do something fast- I go to Breckenridge next weekend with this bike and I want to come back in one piece.
 

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Te mortuo heres tibi sim?
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i dont understand the quesion...... going from 68 or so degrees to 70 as you say you want will be steepening things, making it quicker/sharper/faster/ whatever you want to call it.
which is the opposite of what you'd be doing by putting a taller fork on the bike. that would slacken the angles. which sounds like what you want, in the end.

or you could raise the bars more to get your weight farther up and backwards; though this won't change steering, it can help with less OTB experiences. as would a shorter stem; maybe try a 90mm even. if that cramps you , you can compensate a bit by moving the seat back a bit as well. though this may screw with your seated pedaling position too much for your tastes. and how wide are you bars? i found wider bars give me a much better position for steep techy stuff than narrow bars ever did.

and you say you have 1.5" of spacer *under* the headtube already? or do you mean under your stem, lifting the bars up? a picture or better description of your frame/fork/front end setup would help a lot here.
 

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Yeah, you're backwards on your numbers. 68 degrees IS slacker then 71. If you want your fork to be slacker you need to go lower on your numbers, like 67 or 66 degrees. Which is pretty slack for a trail bike. I mean 66 is about the starting point for a downhill bike. If you rode a 575 with a 71 degree angle, you should be better off with the 68 you have now, unless you don't really have 68 now.

Could be your top tube is to short for you, but most likely you just need to adjust your riding style from what you are use to. But in the end, if you want to go slacker you will need a taller fork.
 

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Discussion Starter · #4 ·
In my rush and shaken-up brains- I got all my head-tube angles backwards.

I'm at 70 or 71 degrees, needing to get closer to 69 degrees. The 575 was also 69 degrees. I got it all backwards- it's what four endos in a single ride will do to a guy:)


I have 1.5 inches of spacers between the stem and the head-tube. I don't even want to re-read my first post. I'm sure I sound quite idiot-like. I'm just trying to slacken my head-tube angle some.

I can try a shorter stem but the fit is nice now- a shorter stem and moving the seat back would not be good since this setup and my seat position feels pretty good actually.

Sorry if I sound confused- I think I may be a little woozy right now. Those fast sweepers and rocky climbs were addictive though and this bike was born for that.
 

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CURB HUCK!!!!!!
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try to get the weight on the back of your bike, either lengthen your fork or get a taller shorter stem and scoot your seat back and you can even lower your seat post slightly
getting some nokian gazza 3.0 tires in the front will help ;)
 

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Discussion Starter · #6 · (Edited)
I measured the stem (not sure if I'm measuring correctly) and it appears to be a 110. It may help if I switch to a 90mm stem and see if that gets my weight back a bit. It still will not slacken the headtube angle but should reduce the tendency to endo at least by a little bit.

A Marzocchi All Mountain 1 fork would have a taller A-C height but I don't think I can get one in this quickly unless I order it first thing Monday morning from someone who has one in stock. The Pike is another option (not sure about the A-C but it's prob more than 500mm) but I'll have to rebuild the front wheel and buy new spokes and a 20mm hub.
 

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Change compression damping

I'm not sure your endo-ing is because the head tube angle is too steep. The few degrees might affect handling, but it shouldn't make such a big difference in how the big handles going down drops. When people I ride with have had this problem on a new bike, I've found that it is more likely to be due to how the fork is adjusted. In particular, if you don't have enough compression damping, the fork blows through its travel too quickly, throwing your weight forward. If you crank up the compression damping a bit, it's a more controlled compression and it doesn't pitch you forward as much. I'm not sure if you have a new fork or not, but even if it worked ok on another bike, it might act differently on this bike. Also, what works well for one rider will pitch another over the bars. So it's worth considering.
 

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Discussion Starter · #8 ·
I'll check my fork. I set it up pretty tight to where it isn't using all its travel but I'll fine tune all the adjustments. I may also use a 90mm stem and try running a bit more sag in the rear shock. The stem may help me quite a bit.
 

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Your X5 is a 2004? I demoed one and found the bike to be a bit tall, tippy, and overly quick. The newer geometry (I demoed the 06 last fall) is better for a trailbike imo. A taller fork will certainly help though. The pike would be a great choice. Also try to find an 06 X5 and see if the geometry suits your needs better. I have also ridden a couple of 575s and they feel lower-slung and more stable than the 04 X5s.

Good luck.
 

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Do you have adjustable rockers? If so, you could also trying dropping to a lower travel setting. This should slacken angles and lower the BB everything else held constant.

Not ideal if you're wed to getting X amount of travel, but may be a cheap and easy way to figure out what solutions may work for you without throwing a bunch of cheddar at it.
 

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agoura_biker said:
I'm not sure your endo-ing is because the head tube angle is too steep. The few degrees might affect handling, but it shouldn't make such a big difference in how the big handles going down drops. When people I ride with have had this problem on a new bike, I've found that it is more likely to be due to how the fork is adjusted. In particular, if you don't have enough compression damping, the fork blows through its travel too quickly, throwing your weight forward. If you crank up the compression damping a bit, it's a more controlled compression and it doesn't pitch you forward as much. I'm not sure if you have a new fork or not, but even if it worked ok on another bike, it might act differently on this bike. Also, what works well for one rider will pitch another over the bars. So it's worth considering.
agree with Dr Agoura Biker
 

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I had a similar issue with my '04 X5. I'm 6' 1" and with the seat at the ideal pedalling height it always felt a bit tippy on very steep downhills. That was the case even with a longer Pike (520 mm A2C) and a 90 mm stem. Increasing rear sag from 25% to over 30% helped a fair bit, but the biggest improvement was adding a Gravity Dropper seatpost. I find it very easy to switch on the fly and use it dozens of times per ride. Never been over the bars since and the bike now feels very stable on steeps. It feels like a DH bike with the seat 3" lower and you can still pedal for short distances until you pop the seat back up. I think you currently have everything working against you with a shorter fork and longer stem.
 

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Sounds like your X-5 is of the '05 and later vintage, if it's sporting a 68.8 deg HA spec'ed with a 505mm a-c fork. The '04 had a 70.3 deg HA spec'ed with a 478mm a-c fork. (The A-C numbers on the Pike are listed on page 2 of stripes' post about the Fox 36.) I am getting ready to sell my '04 Z1 FR, which has a 520mm a-c, which should put you exactly where you want to be on your HA. It also is the QR model so no new wheel. (Also has the ETA, air assist, and high end rebound dampening - HSCV or something like that.) I've decided it's too tall of a fork for my '04 X-5, but it would be perfect for an '05 or later with the slacker HA. PM me if you're interested
 

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Discussion Starter · #15 ·
I'm running too little sag in the rear shock for a 2004 frame, which mine is. I'm running about 15% which is not what the 2004 was probably designed for. I ran around 15%-20% on my 575 depending on the trail but that bike is designed for short sag rates as well. See, here in the Midwest, we have to pedal a lot- there is no climb uphill and then bomb downhill, right? We are constantly pedalling and a 30%-35% sag rate eats up a lot of energy, I would think. A 10 mile ride will have everything thrown in- fast sweepers, tight sweepers, slow technical/rocky sections, rock slabs, tree roots and dips and troughs, and off-camber turns. Then you will hit a looong stretch where it's very smooth for 10 minutes and the Rigid riders start smiling. Then it's back to all of the above.

However, I will adjust my rear shock to the recommended settings and I bet the bike will feel more planted. I'm going to have to start going to the gym again though.
 

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Running 1/2 the amount of sag the bike is designed for will certainly ruin the ride IMO.

Try it at 30% and see how you like it.

Too little sag definitely steepens head and seat angles, raises the BB, and increases the spring rate in the rear.....a recipe for endos.

The X-5 is not a particularly "pedal efficient" bike if that is what you are looking for. The suspension is supple, and works in all conditions to deliver great traction to the rear tire which, again, imo, suspension is supposed to do, and why I love the design. I want traction, not pedal efficiency.

Most pedal efficient bikes sacrifice the rear suspensions ability to react to terrain conditions since the rear is stiffening up under chain torque. This may be a preferable type of design for how you ride. I personally found my Salty stellar in midwest conditions when I rode it out there.

Anyway, try more sag. It will dramatically change the feel of the bike.
 

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Flyer said:
I'm running too little sag in the rear shock for a 2004 frame, which mine is. I'm running about 15% which is not what the 2004 was probably designed for. I ran around 15%-20% on my 575 depending on the trail but that bike is designed for short sag rates as well. See, here in the Midwest, we have to pedal a lot- there is no climb uphill and then bomb downhill, right? We are constantly pedalling and a 30%-35% sag rate eats up a lot of energy, I would think. A 10 mile ride will have everything thrown in- fast sweepers, tight sweepers, slow technical/rocky sections, rock slabs, tree roots and dips and troughs, and off-camber turns. Then you will hit a looong stretch where it's very smooth for 10 minutes and the Rigid riders start smiling. Then it's back to all of the above.

However, I will adjust my rear shock to the recommended settings and I bet the bike will feel more planted. I'm going to have to start going to the gym again though.
15%!!!!!!!!!!!!! Way too stiff. How much travel do you get out of it set like that? What shock are you using? I find the Swinger 3-way air is really good for helping the pedal efficiency. The platform damping reduces bob to a minimum and yet it still feels quite plush through the mid-stroke. I use a Romic coil when I want it super plush and sensitive, but then you do start noticing some pedal bob as a consequence. I run around 30% sag on the Swinger 3-way (5.3" travel) and around 35% on the Romic (6" travel). The bike rides great either way. Your effective BB height must be nearly an inch higher than mine, which will make a huge difference to the handling.
 

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Discussion Starter · #18 ·
I measured it more accurately and am running right at 20%. I need to run more sag either way- that's obviously way too little. I was not aware that the bike was designed around a 33% or 35% sag rate. I figured it was 25% and running it a bit tighter would be fine. It's no surprise that the high BB was making the bike overly twitchy and endo-prone. I'm all adjusted now but the rain showed up so I'll have to wait.

My subject line should have read something like "This 18.67% sag is killing me." :rolleyes: Silly Me!!
I need to get the bike out again. Thanks to everyone for your patient advice while I go through my paradigm shift and experience the more stable side of this bike :)
 

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Flyer said:
I measured it more accurately and am running right at 20%. I need to run more sag either way- that's obviously way too little. I was not aware that the bike was designed around a 33% or 35% sag rate. I figured it was 25% and running it a bit tighter would be fine. It's no surprise that the high BB was making the bike overly twitchy and endo-prone. I'm all adjusted now but the rain showed up so I'll have to wait.

My subject line should have read something like "This 18.67% sag is killing me." :rolleyes: Silly Me!!
I need to get the bike out again. Thanks to everyone for your patient advice while I go through my paradigm shift and experience the more stable side of this bike :)
I find my Salty to be extremely versatile, so not super sensitive to different amounts of sag, but the sag you've been running seems extreme enough it would seem to really affect how the bike rides. Also, don't forget that the front and back need to be balanced. I earlier wrote to check the compression damping, and it sounds like you are running the front with not much sag, too. That might help prevent endos (though it's not the same as having more compression damping), but you might want to play with softening that up, too, to balance out your new plush rear suspension:D

Be sure to give us a ride report once things dry out enough!
 

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Flyer said:
I measured it more accurately and am running right at 20%. I need to run more sag either way- that's obviously way too little. I was not aware that the bike was designed around a 33% or 35% sag rate. I figured it was 25% and running it a bit tighter would be fine. It's no surprise that the high BB was making the bike overly twitchy and endo-prone. I'm all adjusted now but the rain showed up so I'll have to wait.

My subject line should have read something like "This 18.67% sag is killing me." :rolleyes: Silly Me!!
I need to get the bike out again. Thanks to everyone for your patient advice while I go through my paradigm shift and experience the more stable side of this bike :)
I think increasing the rear sag will make a big difference. I still think 110 mm is a very long stem for this bike, so I'd definitely try a shorter one at some point. I also think a 140 or 150 mm fork is better suited to this bike. I find the Pike is a great match for this frame. The 20 mm axle helps make the most of the inherent frame stiffness and adjustable travel is useful for steep climbs.
 
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