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should I upgrade and m I overthinking the trail difference and steep head tube

  • upgrade you'll be fine and more in line with the competitor set

    Votes: 1 33%

  • don't upgrade the geo is too steep and increased trail is going to send you over on any drop

    Votes: 2 67%
  • Total voters
    3
1 - 20 of 24 Posts
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yosshaa

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Discussion starter · #1 ·
Looking for opinions on how upgrading my fork could affect my ride experience

Rider: mostly road pretty terrible mtb, have done 4 marathon races. Brown's Ranch, and McDowell mountain preserve are the two closest places I ride
Bike: Canyon Lux currently with Reba RL 110mm, 51 offset, 69.5 head tube angle, 2.3" tires, 83 mm of trail.
I should say with this bike I have shortened the stem from 80 to 70 and have wider bars 740mm.

Terrain: AZ desert, Loose over hard, nothing too technical mostly nice desert trails, I like going fast. I did take this bike to the Telluride MTB downhill park and would 100% do that again.

Problem statement: The canyon geo is pretty steep, the factory fork is 110mm with an offset of 51 and the head angle is 69.5
I am looking to upgrade to the new 100mm travel Sid Ultimate fork, which has an offset of 44 (only offered in 44) its super light, and a better quality fork.
From what I can tell this will bring my trail number UP to 95mm from 83mm. I want to upgrade but I don't want to be flying over the bars every downhill because I brought the wheel too far in.

Rival XC full suspension bikes and head tube angles from 99 spokes as you can see they are all in the 90's:

Rivalsepic expert (120) blur ssparksuper caliber (110)Epic (100)
Trail99919196106
head tube angle 69.568.568.56967.5

Seems like upgrading the fork would bring my bike more in line with competitor trail numbers but as you can see rivals also offer more slack head tube angles.

By upgrading my fork am I going to make my ride experience worse by bringing the front wheel too far in? What else should I consider? I have considered adding the wolf tooth geoshift angle headset to add more slack but its more money and more weight so I don't want to if I don't have to.

GEO COMPARE DEEP DIVE:
99spokes.com

Compare: 2020 Canyon Lux CF SLX 9.0 Race Team vs Lux CF SL 8.0 vs Santa Cruz Blur S / Carbon C / 29 vs 2021 Scott Spark RC 900 Pro vs Trek Supercaliber 9.8 GX vs Specialized Epic Expert – 99 Spokes

99spokes.com 99spokes.com
 
#3 ·
upgraded my cc 100/100 to 120/100 and the gains and losses are as expected.

-feels safer going fast due to headangle
-more travel means riding faster/more relaxed downhill
-climbing is worse, i have to really push the upper body down

i would go for the 120mm if you dont live for the climb
 
#4 ·
I second x-force. go with the 120 if you dont live for the climb. you can also probably get away with getting a new sid with matching travel to your current fork.

are you looking to get the 35mm stanchion sid? if not i believe the 32mm stanchion sid can be had with the same offset.

I replaced a 120mm reba with 51mm offset that came on my specialized fuse comp carbon with one of the new sids with 35mm stanchions so i had to go 44mm offset. head tube angle was 67.5 beforehand - not sure what it is now. i think i notice the shorter wheelbase ever so slightly when descending but that could be in my head. being that your bike has a steeper HTA to start with the shorter wheelbase may be more noticeable.
 
#5 ·
I put a 44os fork on my 68* HTA 29er singlespeed. It didn't "break the handling", but I didn't like it. It felt planted and calm, but not really in a good way. More....like....I had too little psi in my tire.

I did, however think that adding 20mm to the travel from 120 to 140, and installing a -2* anglset was a positive effect. Brought the hta into the 67-ish range. Im not 100% sure both of these will stay, but it's working for me so far. Capable, but still nimble.

On the flip side:
Going from a 51os to a 44os on my 64.5* hta 170mm FS bike was fantastic all the way around. No perceived downsides.


Edit: I live in PHX and ride many of the same trails you do. If I was building a "Brown's bike" It'd be 120mm, 51os, 67-68* hta. My singlespeed is absolutely the perfect choice for out there, but I still ride black-diamond trails at T100 on it.
I save the 170mm big rig for SoMo.
 
#7 ·
My bike has a 68 degree HTA and runs a 120mm / 51 offset fork. Recently I installed a demo 130mm / 44 offset fork. The AC measurement only changes about 7mm and the HTA slackens by just under half a degree.

What I notice the most with the reduced offset was that that understeer was reduced and that the bike really responds more to leaning. The best adjective I can use is that it wants to carve now, and I love it. I don't notice any sacrifices in slow speed tech either. So if you ride fast and like to push the bike I think the reduced offset is great.

Additionally, I ran 120mm forks on two previous bikes I had that were designed around 100mm and I like them both better with that set up. But at 120mm I think 32mm stanchions are too flexy.

I've since ordered the 120mm Sid and can't wait! 1500g for a 35mm 120mm fork is crazy light and very similar to older 100mm Sid weights. Also, you could always run it at 110mm if you wanted.

While I don't love the name, I think a "downcountry" bike is pretty much ideal for 98% of riding. These are essentially born from light weight XC bikes that people slightly over fork.
 
Discussion starter · #8 · (Edited)
@gsteitz I think you're onto something. My original goal was to upgrade the fork and get the weight down.... currently at 26.5 pounds and with the new 100mm sid that would come down but a good half a pound. The 120 would still be lighter than the reba and have some good benefits in geometry and kush.
 
Discussion starter · #9 ·
Impetus said:
I put a 44os fork on my 68* HTA 29er singlespeed. It didn't "break the handling", but I didn't like it. It felt planted and calm, but not really in a good way. More....like....I had too little psi in my tire.

I did, however think that adding 20mm to the travel from 120 to 140, and installing a -2* anglset was a positive effect. Brought the hta into the 67-ish range. Im not 100% sure both of these will stay, but it's working for me so far. Capable, but still nimble.

On the flip side:
Going from a 51os to a 44os on my 64.5* hta 170mm FS bike was fantastic all the way around. No perceived downsides.

Edit: I live in PHX and ride many of the same trails you do. If I was building a "Brown's bike" It'd be 120mm, 51os, 67-68* hta. My singlespeed is absolutely the perfect choice for out there, but I still ride black-diamond trails at T100 on it.
I save the 170mm big rig for SoMo.
Click to expand...
OK interesting! So what I didn't say was I currently have a gravel bike running 650b 47mm tires... I use that for a lot of browns and McDowell. Upping to 120mm on the lux might make it a bit more adventurous. in truth my bike is at 110 now, I intended on going down to 100 because I don't really use a lot of suspensions... but with the geometry considerations, it might make sense to go to 120.
 
Discussion starter · #10 ·
twodownzero said:
Save your money.

You have an XC bike and what you want is a trail bike. If you want a longer and slacker bike, save and get one rather than spending the money on an "upgrade" that is really minor at best.
Click to expand...
So the new Sid is a "minor upgrade" over the old Reba RL? But I should buy a trail bike because I had an offset question? Believe me buddy if I could use your logic to convince my wife I need to buy a trail bike for mcdowell mountain while shes doing it on a hardtail and I was just there yesterday on my gravel bike, I would.
 
#11 ·
yosshaa said:
So the new Sid is a "minor upgrade" over the old Reba RL? But I should buy a trail bike because I had an offset question? Believe me buddy if I could use your logic to convince my wife I need to buy a trail bike for mcdowell mountain while shes doing it on a hardtail and I was just there yesterday on my gravel bike, I would.
Click to expand...
Yes, replacing one XC fork for another is a minor upgrade at best. Placebo compared to a head angle 4 degrees slacker, longer top tube, shorter stem, wider/more aggressive tires, etc.
 
#12 ·
twodownzero said:
Save your money.

You have an XC bike and what you want is a trail bike. If you want a longer and slacker bike, save and get one rather than spending the money on an "upgrade" that is really minor at best.
Click to expand...
Well, there are plenty of XC bikes that fit his description, too. He just happens to have one of the least "modern" new bikes on the market.

Epic Evo
Scalpel SE
Transition Spur
Intense Sniper T

All of which are short travel, long reach, slack HTA bikes.

Sent from my iPhone using Tapatalk
 
#14 ·
yosshaa said:
@gsteitz I think you're onto something. My original goal was to upgrade the fork and get the weight down.... currently at 26.5 pounds and with the new 100mm sid that would come down but a good half a pound. The 120 would still be lighter than the reba and have some good benefits in geometry and kush.
Click to expand...
Are you sure about these numbers? What does your Reba weigh? That's an incredibly heavy bike to spend the money on a fork to cut weight. If the bike is that heavy, it's likely you could loose much more weight for far less money and not compromise your handling.

Sent from my iPhone using Tapatalk
 
#16 ·
yosshaa said:
I don't think I posed my questions correctly.

Is 44 offset fork with a 70 ea angle a bad combo?
Click to expand...
I personally say the answer is yes.
I found I did not like a short offset fork on a 120mm bike. dropping 10mm AND shortening the offset I think is gonna be weird.

I also say nothing with knobby tires should have a 70* hta. I'd make fixing that (on the cheap) my primary focus.

you mentioned in the original post that the feeling of you going over the bars is a concern. It's important to understand that offset isn't going to change that. the feeling of being over the bike is due in much much larger part to reach and HTA. As twodownzero mentioned the change in offset translates to literally a handful of millimeters in wheelbase.

Short offset was 'invented' to solve the opposite of your problem.
 
Discussion starter · #18 ·
FJSnoozer said:
Are you sure about these numbers? What does your Reba weigh? That's an incredibly heavy bike to spend the money on a fork to cut weight. If the bike is that heavy, it's likely you could loose much more weight for far less money and not compromise your handling.

Sent from my iPhone using Tapatalk
Click to expand...
I'm not trying to compromise my handling, I'm trying to understand the trade off.
By upgrading to the 100mm sid I bring my trail in line with other rival bikes in the category... but with the head tube angle slightly steeper what challenges could I face?

Re bike weight:
Its a carbon full suspension bike (nx/gx group). I have upgraded carbon bars, carbon seat post, lighter wheels, cassette, and a carbon crank which equated to a few pounds drop in weight since I got it. My weight is with cages, pedals and new tires full of sealant. not a super light bike but by all accounts, there are much heavier Mtb bikes out there.

The Reba fork is around 1650 grams give or take (based on what I've seen online), the 100 mm sid is said to be around 1330, 120mm version with 35mm stanchions is around 1500.

bikes weight was done by the same park tools digital scale.

Lux w carbon bars and seat post27lbs -5oz
Lux new config (2021) carbon crank new wheels, lighter pedals26lbs-7 oz
Lux with upgraded sid sl fork 100mm ((projected))25 lbs 13 oz
 
Discussion starter · #19 ·
Bumping my own thread here.
I basically scared myself off of upgrading shock here because the fork I want is a 44 offset (new SID) and mine is a 51 (old reba)... Since then I have come to learn that the higher price point Lux's with the same geometry are shipping with 44 offsets (fox) while being 100mm in travel.
 
#20 ·
I think the reason the new forks are 44mm, even on xc forks, is that it universally works better. Not everyone agrees, but it seems that most do. I prefer the lower offset, 51 feels twitchy to me.

I think it works better on longer and/or slacker bikes, but the lux isn't really crazy short. Maybe short compared to other bikes, but it's loooooong compared to 10ish years ago when 51mm was kinda new.
 
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