Looking at different styles of Mountain Bikes I see that different styles of bikes have different fork travel. DH has very long travel, while enduro and trail have less. Why would having a long travel fork on a trail bike be a disadvantage?

It's mostly a matter of weight and geometry. The 120mm fork on my XC bike performs well enough for its intended riding terrain and keeps the weight to a minimum. The 160mm fork on my all-mountain bike weighs over a pound more.

As far as geometry, looking across the spectrum from XC to DH...the wheelbase gets longer, head tube angle gets slacker, front end sits higher, etc. There is a happy medium for each discipline in regards to geometry. I "over-forked" my all-mountain bike from the stock 150 to 160mm travel to make it sit even higher in the front. The "slack" geometry on my all-mountain bike works great for riding extremely technical terrain, however I wouldn't want to race an XC race on it and I even find it overkill on moderately technical terrain. The same could be said in reverse of my XC bike.

Can't comment since the answer above is very comprehensive.

Oddly enough I recently watched a video by a very popular bike guy on YouTube about his “over forked” trail bike. He did mention the additional weight, but stated that the overall project gave an acceptable performance. His name on YouTube is- Your Favorite Cyclist.

Clint, are you interesting in upgrading to a longer travel fork or bike or just curious of the pros and cons? I never heard of Your Favorite Cyclist and I watch a fair amount of of YT Bike vids. looking at his videos, I am not seeing any of where and how he rides. The hardtail he upgraded from had an entry level 130mm coil fork SR Suntour XCM34, swapped to the Rockshox Domain 170mm air fork. So, sure, he will see the improvement in performance for fast downhills over the Suntour fork. but how fork weight and travel comes into play when you are just riding rolling and handling on tight trails and also when climbing.

Sierra_rider’s hit the main points. I agree with them. I ride a 120mm air fork,100 air shock XC bike as my go to for green and blue trails. Rarely used my 160mm/150mm trail bike since the XC bike is adequate for my riding...on 10-12mi 1000-2000ft routes.

My interest comes from the 80 mm spring fork on my 2004 Trek MTB. Watching the used market I was curious if I could go bigger than it with no adverse effects. Many riders replace good forks with better ones opting to sell the originals. Just keeping my options open.

As to Your Favorite Cyclist, he has some good but basic bike advice.

Clint,Here is a good overforking video...We Put An 180mm Enduro Fork On An XC Bike! | Why NOT To Over Fork Your Bike




Can I overfork my bike and be fine? yourfavoritcyclist



And his comments after overforking to a 170mm fork from a 130 coil.

How is my overforked MTB doing? yourfavoritcyclist

I haven't watched any of his videos, but that sounds way too over-forked IMO. I imagine climbing on something like that would be akin to steering an overloaded wheelbarrow. The geometry is likely all wrong for that fork...the fork being capable of terrain that the rest of the bike isn't.

When I think of an "overfork" I think of something in the +10 or 20mm range. I changed out the air shaft(Fox 36) on my Santa Cruz Hightower to bump the travel from 150 to 160mm...I almost considered 170mm, but am glad I didn't. As it stands right now, I don't want to go any higher on the front end of that bike...my stem is slammed and I think it's the perfect compromise between getting the weight forward on steep climbs, and performance on technical DH. If I didn't have to climb up the hills, I'd be all about a 170mm fork with beefy 38mm stanchions.

SierraRider, yeah I was just about to comment the same points as you; overforking is adding about 30mm to the stock fork max
major alteration of bike geometry. I see in your photos that you ride the chunk in Nor Cal, so you could utilize that amount of travel. My riding is much more sedate, but love the 160mm when I need it in the rock gardens at Annadel blues and any of Skeggs blues! that is about as extreme as I get.

Clint, if you are referring to the Trek 3700 on your profile....

I don’t see a benefit of the a much larger fork on your Trek. you won’t be zooming down anything super chunky on that 26" hardtail.

That said you will see a big improvement, merely by upgrading to a 100-110m modern air fork.

But your straight steerer and integrated headset is a limiting factor for fork upgrades.

FWIW, My first suspension MTB was a 26" Kona hardtail with a 80mm Marzochhi Z2 coil fork. that had limitations, even for me when I was in my late 20s riding the same trails I ride today with my 120mm XC bike!

Yeah, I'm basically SW of Tahoe, so ride lots of the high-country black diamond or double black diamond stuff on the Hightower. IMO, my current set up is just right for those kinda rides. I even occasionally hit some of the technical stuff on my XC bike, but obviously it's quite under-biked for that.

I've ridden at Annadel a few times. Once on my old enduro bike, the rest on a couple of different XC bikes. My current XC bike(SC Blur) worked fine at Annadel, but I definitely was getting beat up in the rocks. I think the sweet spot for there is a shorter travel trail bike.

My objective is really not a longer fork, but a better one. I mostly ride gravel roads, and packed dirt trails, mostly populated with hikers. I don’t jump but small ruts and roots make my bike bounce. I’m not fast enough to make me lose control, but would like a little damping. Almost all newer (read that better) forks will do that but shopping used limits my choice of fork length. I think I could do with anything 130 mm or less without problems. That is the only reason I am considering a new fork.

Thanks for all the suggestions.