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2018 Felt Doctrine 4 XL

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2018 Felt Doctrine 4 XL

Old 09-25-21, 07:51 PM
  #26  
Moisture
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Fitted with a longer stem and 185mm crank arms

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Old 05-15-22, 03:42 PM
  #27  
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I feel like I have spent enough time with this bike so effectively summarize my relationship with it as a whole, and explain more in depth what it is like to ride this machine.

This bike is classified as a machine for "casual racers." I don't see what would set this bike apart from a true hardtail race machine, other than the rider. One review called this bike "a runaway freight train on singletrack, - an effective way to describe this bikes traits indeed. It rolls very quickly over most terrain, with very little acceleration or brake usage required to move at a quick pace, in a straight line or around turns. While side to side cornering is obviously optimized for performance, it's difficult not to not this frames stability. I have to actively remind myself to be more careful with what sort of terrain I try to tackle when switching back to my rigid gravel bike . The frame is absurdly stiff with almost zero compliance . Even vibrations and resonance aren't catered to much with this frame. Clearly the engineers did not have comfort in mind for this bike. But the riding position doesn't detract much from relative long distance riding.

It's designed for a pretty aggressive riding position, with a steep handlebar drop and a stretched out feel over the handlebars to really make the most of the short chainstays and long top tube. The 29" wheels do a brilliant job at mai
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Old 05-15-22, 04:07 PM
  #28  
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I feel like I have spent enough time with this bike so effectively summarize my relationship with it as a whole, and explain more in depth what it is like to ride this machine.

This bike is classified as a machine for "casual racers." I don't see what would set this bike apart from a true hardtail race machine, other than the rider. One review called this bike "a runaway freight train on singletrack, - an effective way to describe this bikes traits indeed. It rolls very quickly over most terrain, with very little acceleration or brake usage required to move at a quick pace, in a straight line or around turns. While side to side cornering is obviously optimized for performance, it's difficult not to not this frames stability. I have to actively remind myself to be more careful with what sort of terrain I try to tackle when switching back to my rigid gravel bike . The frame is absurdly stiff with almost zero compliance . Even vibrations and resonance aren't catered to much with this frame. Clearly the engineers did not have comfort in mind for this bike. But the riding position doesn't detract much from relative long distance riding.

It's designed for a pretty aggressive riding position, with a steep handlebar drop and a stretched out feel over the handlebars to really make the most of the short chainstays and long top tube. The 29" wheels do a brilliant job at maintaining stability over almost anything, with the suspension fork imperceptibly stepping in when needed.

The drivetrain is a 2x11. Overall I like it, even when compared to by 1x11 gravel bike, for the wider gear range which helps the rear cassette feel relatively 'close ratio.' 26x42 on the low end gives you wicked hill climbing gear inches which can essentially only be taken advantage of if your riding position is aggressive enough . On the other hand, this beast will rip 36x11 quite easily on even a slight downhill. I find myself a little too caught up with maintaining chainline and avoiding gear overlap when really thrashing, in comparison to 1x.

The handling is fluid with an approachable, highly exhilarating tendency to oversteer when correctly balanced. The bike is still great fun; a pleasure to ride with excellent feedback and responsive handling even if you are not pushing towards its lofty limits .

Start to approach them, and you'll wonder where or when exactly you will reach the threshold. The bike makes you feel like a superhero to the point where I can't help but feel genuinely scared of the thing. The frame maintains a supreme balance between rider feedback, stability and outright agility throughout a wide variety of trail conditions and riding styles.
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Old 05-15-22, 07:39 PM
  #29  
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You have asked about suspension but I don't see where you stated what is on there now. Is it a Reba? If so, that is a solid fork. Nothing fancy, but well made made and easy to service.
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Old 05-15-22, 08:51 PM
  #30  
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Originally Posted by Kapusta View Post
You have asked about suspension but I don't see where you stated what is on there now. Is it a Reba? If so, that is a solid fork. Nothing fancy, but well made made and easy to service.
Yes, it is. I haven't changed it and don't plan to. I'm very happy with its performance .
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Old 05-16-22, 06:31 AM
  #31  
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Originally Posted by Moisture View Post
Yes, it is. I haven't changed it and don't plan to. I'm very happy with its performance .
Being a 4 year-old fork, I would do a full servicing of it. Rebuild kits is likely under $25, and $40 will get you all the damper and lower leg fluids you will need for a very long time. Only special tool needed is snap-ring pliers.

At the bare minimum, do a lower leg service ASAP, as this is the most critical (and more frequently needed) servicing. And pretty easy.

These forks will perform like new indefinitely if you do regular maintenance (especially the lower leg oil changes), or will be toast in a few years if you donít.
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Old 05-16-22, 07:05 AM
  #32  
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Originally Posted by Kapusta View Post
Being a 4 year-old fork, I would do a full servicing of it. Rebuild kits is likely under $25, and $40 will get you all the damper and lower leg fluids you will need for a very long time. Only special tool needed is snap-ring pliers.

At the bare minimum, do a lower leg service ASAP, as this is the most critical (and more frequently needed) servicing. And pretty easy.

These forks will perform like new indefinitely if you do regular maintenance (especially the lower leg oil changes), or will be toast in a few years if you donít.
Thank you for the recommendation. She is currently in the shop.

Should I ask them to service the fork? The bike has seen relatively little use over the years. Im wondering if it may still be a bit early.
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Old 05-16-22, 07:47 AM
  #33  
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Originally Posted by Moisture View Post
Thank you for the recommendation. She is currently in the shop.

Should I ask them to service the fork? The bike has seen relatively little use over the years. Im wondering if it may still be a bit early.
It is absolutely not too early to change the oil in the lowers. Its like engine oil: If you bought a used car with no odometer and no dipstick to check, and did not know when the oil was last changed, would you hold off on changing the oil? Low or dirty oil in the lowers can cause the bushings to wear out and that is basically the end of the fork ever working like new again. And neglecting this is why most 5 year old forks feel like (and are) garbage.

Many shops don't do full service on forks unless it is a shop that deals with a ton of higher end MTBs. Most ship the fork off to the same places that you could ship it to. They might to a lower leg oil change, though.

But really, a full service is something anyone with even mediocre mechanical skills, some patience, and the ability to follow directions can do.

But if you want to keep it simple and cheaper, you are probably fine just changing the fluids (the damper and lower legs). If you are feeling particularly lazy, just do the lowers (though the damper in that fork is even easier to do... though less likely to need it and with lower consequences when neglected). As long as you keep the fluids clean, the worse that will happen by not doing a rebuild on a fork that needs it is a drop on performance: damper fluid draining into the lowers and hydro locking it, loss of damper function, sticky or leaky air piston... all things that are fixable.

It looks like that fork (like so many other open bath RS forks) uses 5 weight in the damper and 15 in the lowers.

For the lowers, there are many options as to what to use (it is only lubricating) and there are countless discussions out there on what the perfect slippery elixer is, but honestly, what you use is far less important than the fact that you simply do it. This is like the oil in your car engine. 98% of it is simply doing it at all. I've used a bunch and they all seem pretty similar to me. I am currently using Maxima Plush 10 weight (different manufacturers measure the viscosity differently). I've also used the Maxima Fork Oil (green label) in 15W, and some formulations of synthetic Castrol and Motorex engine oils based on recommendations. They all work.

Also, while you have the legs off of the fork, check to see if the foam rings (if present) are dirty. If so, clean or replace them (along with the wiper seals). again, not hard.

For damper fluid, I have used Maxima 5 weight fork oil (the green labeled bottle) in all my open bath RS forks (Reba has an open bath damper). You can probably just unscrew the Motion Control damper from the top of the fork leg and look to see if the fluid is clean. But if you want to be sure and also know that the level is correct, empty the old oil out and put in the recommended amount. https://biketechtools.com/forks/oil-...ox/select-fork
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Old 05-27-22, 11:32 AM
  #34  
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Kapusta Hello mr. cabbage,

thank you again for the information.

I spoke to my LBS. Since this bike hasn't seen all that many hours since its inception, we decided that it should be OK to perform the lower leg service at the end of this season.
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