F4 MTB Drive Train Recommendations

BethZ

Active Member
I am looking to convert the 3-front/9-rear drive train to a single front/11 or 12-rear with a new drive train groupset on my 2008 F4 CO2 SL hardtail. Any recommendations? I like SRAM but not sure what is compatible. Thanks!
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black lightning 1987

Moderator
Staff member
The first thing I would do is check your rear hub and see if it's going to be compatible with 11/12. Are you going to want to invest in a new wheel (or pair) in order to make the component swap?
 

JohnnyD

Well-Known Member
Second thing to check is you budget! But in a nutshell the cost with quality parts from reputable sellers will be in the $200-300 range for 1x11 using your existing crankset(it looks to be a 104 BCD 4 bolt crank so you have to check to make sure it is before attempting to reuse it). 1x12 will be north of 300 with a new all SRAM crank, BB , NX Shifter, rear derailleur and NX PG-1230 cassette. I've got the prices on this setup somewhere on my desk.

As for you rear hub compatibility. THEORETICALLY your 9 speed hub should be OK to use. But like most things bike related. Make sure to check ,recheck and recheck again.
 

JohnnyD

Well-Known Member
Sent you a PM to hopefully help you clear up the crazy mess that can come from doing a 1x conversion, but I must offer my real thoughts on what you should do.
" It is my opinion is to leave everything alone, unless it is broken or you need a wider range rear cassette for hill climbing."

I do want to help you if you choose to do it, but I feel it's necessary to make sure you are informed as to what is involved as far as the BASIC parts and the costs of them currenty.
 

black lightning 1987

Moderator
Staff member
" It is my opinion is to leave everything alone, unless it is broken or you need a wider range rear cassette for hill climbing."
I would certainly agree - if it was my bike and everything was functional. It wasn't clear what the OP was trying to achieve with the change to 1 x 11/12.
 

JohnnyD

Well-Known Member
She cleared up why she is interested in it to me the PM I sent her. In a nutshell, The SRAM X7 has never been really dialed in on the front, despite two bike shops having tuned it. So she pretty much keeps it on the large ring up front and shifts the rear. So basically she has a 1x9 setup already, but without the wider range that the modern systems offer and a 44T chainring! I don't know what gearing her crankset is, but most 9 speeds were 22/24, 32/34 , 44/46 from what I've read. Figure the rear is an 11-32 most likely since that was pretty common as well and you can see why she has trouble riding on trails and climbing hills.
 

black lightning 1987

Moderator
Staff member
I am still not clear on exactly what you have on the bike now. You said Shimano but Johnny said you have a SRAM front derailleur. Do you have SRAM shifters or Shimano? If you have a SRAM derailleur and a Shimano shifter, that is likely the cause of your front shifting problem. Swap the SRAM out for a Mega9 and you should fix the problem.
 

BethZ

Active Member
The gear shifters and derailleurs are all SRAM, but it looks like the crank set (if that is the correct term) is a Shimano Mega-9. I wouldn't mind so much if only the front gears worked right. They make a gd awful grinding sound and they don't shift cleanly (I have to press the shifter 2 or 3 times to shift down). I don't know what it needs (new chain or new everything?)
 

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JohnnyD

Well-Known Member
Hi all. Thanks for all the information! I'm looking at the SRAM Eagle GX groupset - https://www.worldwidecyclery.com/bl...ltimate-review-guide-sram-gx-eagle-drivetrain

What is on the bike currently is a Shimano Mega-9 drive train.
View attachment 8384View attachment 8384
You can not use that groupset with your bike. It is for boost spacing. However you can use the NX/GX Eagle set
.
This crankset will work, but you must also purchase this bottom bracket

You can order the above crankset and groupset I listed separately above as one whole set, but they are currently out of stock at worldwide cyclery. You also would need to buy the bottom bracket I mentioned for this as well. Numerous people have done this conversion on other bikes. The key is to MAKE sure that you are getting a NON boost crank and the Eagle NX pg-1230 cassette.
 

BethZ

Active Member
I reached out to Worldwide Cyclery. They were really great, and answered all my questions. Anyway, I ordered the groupset, crank and bottom bracket. I even got 10% off using CapitalOne. I'm super excited! Thanks JohnnyD!
 

JohnnyD

Well-Known Member
Great news. Now the question remains, will you get yours before mine arrives? All I got for the $500.12 spent was a couple more reward points on my CC. 10% off would've been better.

Be sure to reach out once you get it and ready to install it. Honestly, a lot of people are terrified of bike maintenance for NO reason. Except for a few jobs that require REALLY high priced tools and very special knowledge ,like re-facing/re-tapping the bottom bracket, rebuilding a HeadShok or Lefty fork to name a few. I really believe that anyone can learn to do it.
I can tell you lots of stories from when I was in the Air Force fixing fighter aircraft of people who had absolutely no mechanical knowledge that quickly picked up fixing jets after they enlisted. All it takes is the desire to learn/educate yourself and the courage to try.
 
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BethZ

Active Member
Great news. Now the question remains, will you get yours before mine arrives? All I got for the $500.12 spent was a couple more reward points on my CC. 10% off would've been better.

Be sure to reach out once you get it and ready to install it. Honestly, a lot of people are terrified of bike maintenance for NO reason. Except for a few jobs that require REALLY high priced tools and very special knowledge ,like re-facing/re-tapping the bottom bracket, rebuilding a HeadShok or Lefty fork to name a few. I really believe that anyone can learn to do it.
I can tell you lots of stories from when I was in the Air Force fixing fighter aircraft of people who had absolutely no mechanical knowledge that quickly picked up fixing jets after they enlisted. All it takes is the desire to learn/educate yourself and the courage to try.
 

BethZ

Active Member
Well the the bottom bracket tool and cable cutters alone plus cable housing would have cost me another $100. After watching the video by Park Tools -
on how to install this groupset, I saw more necessary tools that I would have to buy. I think the bike shop up the road could install it for way less.
 

JohnnyD

Well-Known Member
I would hope they would at least be competitive to that price point.Great idea to watch the tech videos on how to do it from SRAM as well as the Park Tools videos. Even if you aren't doing the maintenance yourself, it is never a bad idea to educate youself on what exactly you are paying someone else to do for you. Then you have some idea of what they are going to be doing.

I'd have to check my receipts too see how much I paid for new cable housing, cutters, cassette tool, chain wrench, etc.. but off the top of my head everything is right around the $100-125 range for everything that I use for my other bikes. The cost of tools became a "is this worth X amount of dollars" kind of thing to me. Like everyone else, time=money and to me. I am not in that much of a hurry to get my bike up and running since I have two others that I can ride right now, plus two more that are just waiting on me to finish. To do this installation myself I only had to buy a new bottom bracket tool for the DUB BB which was $30ish. For me though that is a cost I am OK with, since I do all my own bike repairs(except rebuilding a HeadShok!). I found a really good deal on bottom bracket facing and thread tap that I will be picking up soon(before the rebuild starts on the Delta V 600) so I can even do that eventually.
 

BethZ

Active Member
Oops, that video was SRAM, not Park Tools. I figure I will build up my tool inventory bit by bit. This seems to be a lot up front.
 

JohnnyD

Well-Known Member
Since I just purchased the same items. Buying all the tools at the same time as well is certainly hard on the wallet. Once your bike is all setup and you've enjoyed a few trails this season, then you can begin to buy yourself the tools.
 

BethZ

Active Member
So, just reading some things about NX vs. GX.

Cassette​

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One of the biggest differences between the NX and GX lines is in the cassettes. The NX cassette features loose gears with plastic spacers between them and fits on your standard freehub body with splines.

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The GX cassette upgrades to pinned cogs, so the cassette is one piece.

It also features a 10-50 range, whereas the NX cassette is an 11-50 range.


Sounds like the GX cassette is the better way to go. I could upgrade it down the road.
 

JohnnyD

Well-Known Member
To upgrade to the GX cassette you would have to change the freehub body on your rear wheel. Depending on what brand of hub you have you might able to find one that has an XD ( SRAM's proprietary freehub body) . The other options are to find a 135 mm QR rear hub with an XD driver like you current rear wheel has and have the wheel relaced, or you can find the rare as hen's teeth 26" rear wheel with one already equipped with one. The small differences between the NX and GX cassettes aren't worth the huge costs involved. The 11-50 tooth has a range of 454ish%, the 10-50T is 500% range, for MOST riders that is pretty much equal. Converting that to an easily understandable concept, like MPH. at 60 RPM(one crank revolution a second)
11-50T give you 13.5 MPH in the highest gear and 3 MPH in the lowest gear
10-50T give you 14.8 MPH and again 3.0 in the highest.
The biggest difference between the two are in weight due to materials used.
The NX cassette uses steel gears(615g) vs the aluminum on the GX (450g). to me that is a minor amount of weight
 

BethZ

Active Member
To upgrade to the GX cassette you would have to change the freehub body on your rear wheel. Depending on what brand of hub you have you might able to find one that has an XD ( SRAM's proprietary freehub body) . The other options are to find a 135 mm QR rear hub with an XD driver like you current rear wheel has and have the wheel relaced, or you can find the rare as hen's teeth 26" rear wheel with one already equipped with one. The small differences between the NX and GX cassettes aren't worth the huge costs involved. The 11-50 tooth has a range of 454ish%, the 10-50T is 500% range, for MOST riders that is pretty much equal. Converting that to an easily understandable concept, like MPH. at 60 RPM(one crank revolution a second)
11-50T give you 13.5 MPH in the highest gear and 3 MPH in the lowest gear
10-50T give you 14.8 MPH and again 3.0 in the highest.
The biggest difference between the two are in weight due to materials used.
The NX cassette uses steel gears(615g) vs the aluminum on the GX (450g). to me that is a minor amount of weight
I was also thinking about the crankset. Just because my bike currently has a 170mm, does it mean that’s what I should have for my height? I am just 4’11 1/2” to under 5’ tall and 61 yo. Maybe I should have a smaller crankset size?
 
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