# Weight of my new bike



## Fatina (May 8, 2021)

Yesterday I got my first full suspension mtb: a trek fuel ex 8. I come from an x caliber 8 and at the bike shop we found out that the weight is about the same for both. However, after some riding today, I really felt the fuel ex "heavier". I'm not really sure if it's just because it's overall bigger, but there is something weird, especially on the front. Of course, during descents, the exi s a totally different beast but while I was expecting a more sluggish feeling, I really didn't expect this heavyness and I wonder if it may be just because of the 2.6 tires it comes with or something else.


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## natemeister (Jan 16, 2021)

Yea those tires are much heavier and that's rotating weight. With that extra weight comes benefits of the larger size and more durable casing.


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## RETROROCKS (Sep 25, 2004)

Sounds like you have downhill tires on the bike, they are very heavy and overkill for trail riding.
The fork could also be heavier not sure what the bike setup is. But the tires are a great place to start may have heavy tubes in them as well!!


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## Fatina (May 8, 2021)

RETROROCKS said:


> Sounds like you have downhill tires on the bike, they are very heavy and overkill for trail riding.
> The fork could also be heavier not sure what the bike setup is. But the tires are a great place to start may have heavy tubes in them as well!!


They are the stock trek fuel ex tires. They Are also tubeless. I thought the 2.6 in the front was kinda overkill but the bike came with it.


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## Riled (May 1, 2012)

I'm guessing your bike is a 29", and if so the tire weight only changed from 770g (per tire) to 945. That's not that big of a change, and 945g is a very reasonable tire weight on today's bikes. Also, your old tires were not tubeless according to Trek (but they may have been converted?), but your new ones are. If they're set up tubeless, the weight difference will be even smaller (probably less than 100g). Your new tires also have a more supple casing (120 tpi vs. 30!) and that combined with more width has been shown to be capable of less rolling resistance.

Long story short - I don't think it is your tires; or at least it doesn't need to be. Make sure your new tires are actually set up tubeless, and then run as low of a pressure in them as you safely can. I weight 170 lbs with my gear and run 27.5" x 2.6s at about 17 psig plain, or 15 with a protective liner. I could actually go lower probably, but I'm being conservative since I have carbon rims that I can't risk.

A couple of alternative theories:

Fork: The old bike had a Judy SL vs. the new with a Fox Rhythm 34. Your new fork is more supple at the top end and you may be feeling more motion and less support from the front. Make sure your compression and rebound is set properly for what you prefer. Make sure the air spring pressure gives you the proper sag, and maybe aim for less sag if a range is given.
Shock: Even though you say the weirdness comes from the front of the bike, you are on full sus now and may be feeling pedal bob. That can rob a little bit of energy, and it's possibly what you're noticing. Ride the bike with the rear locked-out and see how it feels. If it feels "fixed" then turn the shock back on, make sure that the shock is set up properly for your weight and riding style (maybe increase compression damping and raise air pressure a touch), and try to get used to the feeling. Full sus is what you paid for and it's going to overall be a better experience once you adjust.
Geometry: This is where I would bet my money. It looks like you went from old school to new school bike geo. Effective seat tube angle got 2 degrees steeper and head tube angle got about 4 degrees slacker. Wheelbase got 7 inches longer (177 mm longer!). That's a pretty massive change. You can put the flip chip in High which will steepen everything by about 0.5 degrees, and since it's the slack head angle that you're feeling, steeper would maybe help. The heaviness you're feeling is probably the longer wheelbase and less precise low-speed steering. The bike is way more stable (and safe) than your old one, but may feel a little vague at low speeds.
This is just my guess from having gone through a similar transition recently.


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## Fatina (May 8, 2021)

Omg thank you very much for this very detailed answer. I think you nailed the third point. I feel this heaviness mostly at low speeds! I guess I should just get used to it. On the x caliber I replaced my tires with maxxis 2.3 so they were probably heavier than stock (and no tubeless). I think you are right, it's not the tires.


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## Hardrake (Apr 25, 2015)

Replace your rear tire with a Maxxis Rekon 2.6 tire. That will fix the problem. The Rekon weighs about 800 grams and the tread pattern is cross country suited but able to handle rugged trails. Two things will happen: your rear wheel will be lighter and you will be happier.


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## ehayes (Jun 25, 2019)

Hardrake said:


> Replace your rear tire with a Maxxis Rekon 2.6 tire. That will fix the problem. The Rekon weighs about 800 grams and the tread pattern is cross country suited but able to handle rugged trails. Two things will happen: your rear wheel will be lighter and you will be happier.


I second the Rekon suggestion. I have a 27.5x2.6" Rekon on my SC 5010's rear wheel and it works out great. Like the other post above, I also run the lowest pressure I can, usually mid-teens in PSI.


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