Is it "reasonable" to make my Fat Bike lighter?
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Is it "reasonable" to make my Fat Bike lighter?
I weighed my bike w/o wheels and included my empty frame bag, Manitou Mastodon, dropper post, and Surly Moloko bars. The weight was ~22 lbs.
I checked the weight of my two wheelsets: One fatboy rims with 26 x 4.0 Vanhelgas: ~16 lbs for the set. For my 29+ Mulefut with 2.6 Purgatory/Butcher tires: 11 lbs for the set.
Both have a 10 speed 11-42 cassette (one Sunrace one Shimano) and 203/180mm rotors.
Without going to carbon or to any components that would be great for an XC race but sketchy for trail riding, do I have reasonable options for getting the weight down primarily on the wheels?
I checked the weight of my two wheelsets: One fatboy rims with 26 x 4.0 Vanhelgas: ~16 lbs for the set. For my 29+ Mulefut with 2.6 Purgatory/Butcher tires: 11 lbs for the set.
Both have a 10 speed 11-42 cassette (one Sunrace one Shimano) and 203/180mm rotors.
Without going to carbon or to any components that would be great for an XC race but sketchy for trail riding, do I have reasonable options for getting the weight down primarily on the wheels?
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The basics (which you probably know) are drilled rims and tubeless.
From there you could look to further drilling rims if possible or lighter spokes - but those would just be grams and probably not worth the effort.
Or look for lighter tires.
Although you said no carbon...
After that the biggest weight savings would probably be swapping out the steel Surly bars for light alloy or carbon flatbar with similar bar ends.
Check the saddle weight and swap out for a light one if applicable.
Carbon or light alloy seat post (dropper adds weight).
Carbon rigid fork (again, suspension adds weight).
Go 1x to lose some drivetrain weight.
The problem being that adding suspension, moloko bars and dropper post probably added exponentially more weight than any saving from an already tubeless drilled wheelset could ever yield. I know, not what you were looking for.
From there you could look to further drilling rims if possible or lighter spokes - but those would just be grams and probably not worth the effort.
Or look for lighter tires.
Although you said no carbon...
After that the biggest weight savings would probably be swapping out the steel Surly bars for light alloy or carbon flatbar with similar bar ends.
Check the saddle weight and swap out for a light one if applicable.
Carbon or light alloy seat post (dropper adds weight).
Carbon rigid fork (again, suspension adds weight).
Go 1x to lose some drivetrain weight.
The problem being that adding suspension, moloko bars and dropper post probably added exponentially more weight than any saving from an already tubeless drilled wheelset could ever yield. I know, not what you were looking for.
Last edited by Happy Feet; 01-01-20 at 11:40 PM.
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So after having time to look at it I looked at my fat bike rims and tubes. My Fatboy rim weighs ~887.5g average between the two, and the Surly inner tube weighs 300g. If I were to rebuild the rims around the Fatback Big Su and add *enough* sealant for the tires (for me) It would be 640g + 160g with 150ml of sealant. The weight difference would then be 397.5g for a wheel, or 795g for both wheels (~1.75lbs weight savings).
The reason why I wanted to focus on the wheels is, well I added the dropper post and sus. fork to make my fat bike a better trail MTB. The bars are a comfort thing, however the tires and the rotational weight are the things that I really wanted to target. The main thing I was concerned with was seeing how much rotational weight could I shed, and how much weight would be significant enough to warrant the money required to make the tires lighter?
The reason why I wanted to focus on the wheels is, well I added the dropper post and sus. fork to make my fat bike a better trail MTB. The bars are a comfort thing, however the tires and the rotational weight are the things that I really wanted to target. The main thing I was concerned with was seeing how much rotational weight could I shed, and how much weight would be significant enough to warrant the money required to make the tires lighter?
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So after having time to look at it I looked at my fat bike rims and tubes. My Fatboy rim weighs ~887.5g average between the two, and the Surly inner tube weighs 300g. If I were to rebuild the rims around the Fatback Big Su and add *enough* sealant for the tires (for me) It would be 640g + 160g with 150ml of sealant. The weight difference would then be 397.5g for a wheel, or 795g for both wheels (~1.75lbs weight savings).
The reason why I wanted to focus on the wheels is, well I added the dropper post and sus. fork to make my fat bike a better trail MTB. The bars are a comfort thing, however the tires and the rotational weight are the things that I really wanted to target. The main thing I was concerned with was seeing how much rotational weight could I shed, and how much weight would be significant enough to warrant the money required to make the tires lighter?
The reason why I wanted to focus on the wheels is, well I added the dropper post and sus. fork to make my fat bike a better trail MTB. The bars are a comfort thing, however the tires and the rotational weight are the things that I really wanted to target. The main thing I was concerned with was seeing how much rotational weight could I shed, and how much weight would be significant enough to warrant the money required to make the tires lighter?
https://www.speedgearbike.com/439078.../nextie-carbon
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For me too. Since bikes became the new "it" I'm amazed at the price people are willing to spend on them.
One problem I see with trying to go light light weight in this case is the strength penalty you may pay, considering the rider weight. Sometimes people run fairly light systems like lower spoke counts or thinner rim material but then turn out to be riders in the about 140 -160lb's range. For a heavier rider, or a bike that is going to see hard use I personally would err a bit on the conservative side for build strength.
Not to say one can't be light and strong but the cost for that tends to go up quite a bit.
After looking at a light wheelset and going tubeless, I would focus on the tires. A light set that has good (low) rolling resistance can make quite a difference and be factored into the general cost of consumables so as not to be a big hit in the pocketbook. It's an upgrade/change I plan to do next spring for my fatbike while using what have through the winter when snow and mud make rolling resistance somewhat moot.
One problem I see with trying to go light light weight in this case is the strength penalty you may pay, considering the rider weight. Sometimes people run fairly light systems like lower spoke counts or thinner rim material but then turn out to be riders in the about 140 -160lb's range. For a heavier rider, or a bike that is going to see hard use I personally would err a bit on the conservative side for build strength.
Not to say one can't be light and strong but the cost for that tends to go up quite a bit.
After looking at a light wheelset and going tubeless, I would focus on the tires. A light set that has good (low) rolling resistance can make quite a difference and be factored into the general cost of consumables so as not to be a big hit in the pocketbook. It's an upgrade/change I plan to do next spring for my fatbike while using what have through the winter when snow and mud make rolling resistance somewhat moot.
Last edited by Happy Feet; 01-03-20 at 07:20 PM.
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https://www.speedgearbike.com/439078...9851/hed-b-a-d
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#9
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"Without going to carbon or to any components that would be great for an XC race but sketchy for trail riding, do I have reasonable options for getting the weight down primarily on the wheels?"
_____________________________
(IMO) It depends on your pocket book priorities (but I wouldn't equate carbon components or frame JUST for racing)...like others above, consider a wheelset?
My first fatty was a heavy first edition alloy Mukluk with wheel cut outs.
Next was a rigid cf Beargrease that came with a 26" Whisky rim wheelset (cf) that I rode on a supported GDMBR from Banff to Antelope Wells, with 3.0" WTB Rangers & the Whisky rims are still being used on the newest (rigid Fatback Corvus with Jones bars and dropper) w/ 4.5" wide beists, tubeless during winter. (and those wheels have never needed anything other than cleaning since purchase and over 5K miles on 'em-mostly dry turf).
Summer time I switch to 27.5 X 2.8" tubeless (on an alum WTB wheelset-DTS hubs, built by my LBS) that I ride everywhere including Moab as my only mtb that rides, that I find very acceptable-preferable to a suspension (and I'm no spring chicken AND don't ride the very very uber tough technical terrain).
I've never weighed the summer nor winter bike set up since it is light enough for bikepacking.
Good luck.
_____________________________
(IMO) It depends on your pocket book priorities (but I wouldn't equate carbon components or frame JUST for racing)...like others above, consider a wheelset?
My first fatty was a heavy first edition alloy Mukluk with wheel cut outs.
Next was a rigid cf Beargrease that came with a 26" Whisky rim wheelset (cf) that I rode on a supported GDMBR from Banff to Antelope Wells, with 3.0" WTB Rangers & the Whisky rims are still being used on the newest (rigid Fatback Corvus with Jones bars and dropper) w/ 4.5" wide beists, tubeless during winter. (and those wheels have never needed anything other than cleaning since purchase and over 5K miles on 'em-mostly dry turf).
Summer time I switch to 27.5 X 2.8" tubeless (on an alum WTB wheelset-DTS hubs, built by my LBS) that I ride everywhere including Moab as my only mtb that rides, that I find very acceptable-preferable to a suspension (and I'm no spring chicken AND don't ride the very very uber tough technical terrain).
I've never weighed the summer nor winter bike set up since it is light enough for bikepacking.
Good luck.
Last edited by stormpeakco; 01-07-20 at 07:37 AM. Reason: typo
#10
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Lose rotational weight?
On the Farley 9.6 that I have has 27.5 Sun Ringle Mulefut 80 rims. [who came up with this screwy name for a rim?]
Go tapeless and tubeless using 4 bottles of crazy glue and silicone.
Crazy glue the rim strip on each side and lay it out thick hence one bottle per side. Ok, crazy glue the rim strip on the inside of the rim only, both sides. Any manufacturing holes in the rim plug with a dab of silicone. If by chance there are leaks crazy glue the rim strip on the outside of the rim with a little air in the tire to help set the glue.
This setup works for me I ride year-round @ 4 k per year.
At times I need to add more stans.
You save the weight of the tubless tape @ 75 grams
Use 4 ounces of stans per wheel. The crazy glue weights next to nothing.
Good Luck
On the Farley 9.6 that I have has 27.5 Sun Ringle Mulefut 80 rims. [who came up with this screwy name for a rim?]
Go tapeless and tubeless using 4 bottles of crazy glue and silicone.
Crazy glue the rim strip on each side and lay it out thick hence one bottle per side. Ok, crazy glue the rim strip on the inside of the rim only, both sides. Any manufacturing holes in the rim plug with a dab of silicone. If by chance there are leaks crazy glue the rim strip on the outside of the rim with a little air in the tire to help set the glue.
This setup works for me I ride year-round @ 4 k per year.
At times I need to add more stans.
You save the weight of the tubless tape @ 75 grams
Use 4 ounces of stans per wheel. The crazy glue weights next to nothing.
Good Luck
Last edited by dougiet; 01-11-20 at 03:09 PM. Reason: clarify, word 'strip' for word 'tape' is misleading.
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Lose rotational weight?
On the Farley 9.6 that I have has 27.5 Sun Ringle Mulefut 80 rims. [who came up with this screwy name for a rim?]
Go tapeless and tubeless using 4 bottles of crazy glue and silicone.
Crazy glue the rim tape on each side and lay it out thick hence one bottle per side. Ok, crazy glue the rim tape on the inside of the rim only, both sides. Any manufacturing holes in the rim plug with a dab of silicone. If by chance there are leaks crazy glue the rim tape on the outside of the rim with a little air in the tire to help set the glue.
This setup works for me I ride year-round @ 4 k per year.
At times I need to add more stans.
You save the weight of the tubless tape @ 75 grams
Use 4 ounces of stans per wheel. The crazy glue weights next to nothing.
Good Luck
On the Farley 9.6 that I have has 27.5 Sun Ringle Mulefut 80 rims. [who came up with this screwy name for a rim?]
Go tapeless and tubeless using 4 bottles of crazy glue and silicone.
Crazy glue the rim tape on each side and lay it out thick hence one bottle per side. Ok, crazy glue the rim tape on the inside of the rim only, both sides. Any manufacturing holes in the rim plug with a dab of silicone. If by chance there are leaks crazy glue the rim tape on the outside of the rim with a little air in the tire to help set the glue.
This setup works for me I ride year-round @ 4 k per year.
At times I need to add more stans.
You save the weight of the tubless tape @ 75 grams
Use 4 ounces of stans per wheel. The crazy glue weights next to nothing.
Good Luck
If I am reading right:
You use only one wrap of rim tape instead of two or three and accounting for the loss of overlap / full coverage by crazy gluing that single wrap in place?
Just trying to visualize it.
Thanks.
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How much does drilling the rims actually save?
I don't think the aluminum rim was a major part of the weight of my Mongoose Massif wheel weight. I have a bare rim somewhere I could weigh. Does drilling also mean thicker rim tape?
I don't think the aluminum rim was a major part of the weight of my Mongoose Massif wheel weight. I have a bare rim somewhere I could weigh. Does drilling also mean thicker rim tape?
#13
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Reply to Happy Feet
It is the elastic rim strip or tape without the glue that stretches over the rim to protect the inner tube from the ends of the spokes. On Sun Ringle Mulefut 80 rim you can see this strip or tape popping out of the rim cutouts. They come in different colors like black, green, yellow for example. Crazy glue this both sides inside the rim. Dab silicone if there are little holes in the rim. When the time comes to replace the rim strip or tape use a knife and a wire wheel, an easy job to do.
The tubeless tape is used to complete a tubeless wheelset up, no tubeless tape is used with this example. Go tubeless and not gain the 75 or so grams of rotational weight added to the wheel using tubeless tape.
It is the elastic rim strip or tape without the glue that stretches over the rim to protect the inner tube from the ends of the spokes. On Sun Ringle Mulefut 80 rim you can see this strip or tape popping out of the rim cutouts. They come in different colors like black, green, yellow for example. Crazy glue this both sides inside the rim. Dab silicone if there are little holes in the rim. When the time comes to replace the rim strip or tape use a knife and a wire wheel, an easy job to do.
The tubeless tape is used to complete a tubeless wheelset up, no tubeless tape is used with this example. Go tubeless and not gain the 75 or so grams of rotational weight added to the wheel using tubeless tape.
Last edited by dougiet; 01-11-20 at 06:38 PM. Reason: clarify
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Reply to Happy Feet
It is the elastic rim strip or tape without the glue that stretches over the rim to protect the inner tube from the ends of the spokes. On Sun Ringle Mulefut 80 rim you can see this strip or tape popping out of the rim cutouts. They come in different colors like black, green, yellow for example. Crazy glue this both sides inside the rim. Dab silicone if there are little holes in the rim. When the time comes to replace the rim strip or tape use a knife and a wire wheel, an easy job to do.
The tubeless tape is used to complete a tubeless wheelset up, no tubeless tape is used with this example. Go tubeless and not gain the 75 or so grams of rotational weight added to the wheel using tubeless tape.
It is the elastic rim strip or tape without the glue that stretches over the rim to protect the inner tube from the ends of the spokes. On Sun Ringle Mulefut 80 rim you can see this strip or tape popping out of the rim cutouts. They come in different colors like black, green, yellow for example. Crazy glue this both sides inside the rim. Dab silicone if there are little holes in the rim. When the time comes to replace the rim strip or tape use a knife and a wire wheel, an easy job to do.
The tubeless tape is used to complete a tubeless wheelset up, no tubeless tape is used with this example. Go tubeless and not gain the 75 or so grams of rotational weight added to the wheel using tubeless tape.
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#17
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So after having time to look at it I looked at my fat bike rims and tubes. My Fatboy rim weighs ~887.5g average between the two, and the Surly inner tube weighs 300g. If I were to rebuild the rims around the Fatback Big Su and add *enough* sealant for the tires (for me) It would be 640g + 160g with 150ml of sealant. The weight difference would then be 397.5g for a wheel, or 795g for both wheels (~1.75lbs weight savings).
The reason why I wanted to focus on the wheels is, well I added the dropper post and sus. fork to make my fat bike a better trail MTB. The bars are a comfort thing, however the tires and the rotational weight are the things that I really wanted to target. The main thing I was concerned with was seeing how much rotational weight could I shed, and how much weight would be significant enough to warrant the money required to make the tires lighter?
The reason why I wanted to focus on the wheels is, well I added the dropper post and sus. fork to make my fat bike a better trail MTB. The bars are a comfort thing, however the tires and the rotational weight are the things that I really wanted to target. The main thing I was concerned with was seeing how much rotational weight could I shed, and how much weight would be significant enough to warrant the money required to make the tires lighter?
UPDATE: Well I've just gotten my first flat with my fancy expensive tube... It's a super slow leak and I have no idea what's causing it. I'll update more once I know, but maybe these things aren't as durable as I hoped!
Last edited by DuneRider; 01-19-20 at 02:37 AM.
#19
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I was cursed with flats until I mounted some Surly Knards. So far, no punctures
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If you do decide to go the tubeless route, make sure you don't ride with the pressure TOO low otherwise you'll unseat the bead when you hit a bump and you'll get a lovely spray of goo all over your clothing and frame. :-)
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I'd say 1.75lbs is pretty noticeable on the wheels and you'd be happy to lose it.. Especially off jumps the bike will feel much less rigid and more maneuverable IME. I have Mulefut 80's with 4.8" Jumbo Jim's and was able to get away with 60ml of Stans Race Seal per wheel. I taped the rims with one layer of Tyvek tape, and one layer of OEM Sun Mulefut tape. After about one week of that setup I bombed into a creekbed with super low PSI and smashed my rear rim to the point of cracking and having a big flat spot. The tubeless setup went to hell with that, not a good seal on the bent up rim. So instead of dropping $300 on a new wheel, I hammered the rim as straight as I could get it then put in a 159 gram Revoloop.fat tube. I had to order it from Germany and it was like $50 for a tube when you add in the DHL shipping, but it pretty much weighs the same as my tubeless setup when you account for tape, valve stem, and sealant. It's been just over 2 weeks and so far so good with the tube. I got it from a website called r2-bike.com if you're interested. For me it was worth $50 to save over 150 grams of rotational weight... But maybe I'm just bad with money! : )
UPDATE: Well I've just gotten my first flat with my fancy expensive tube... It's a super slow leak and I have no idea what's causing it. I'll update more once I know, but maybe these things aren't as durable as I hoped!
UPDATE: Well I've just gotten my first flat with my fancy expensive tube... It's a super slow leak and I have no idea what's causing it. I'll update more once I know, but maybe these things aren't as durable as I hoped!
#23
Senior Member
Saving weight with a price ratio of $1 per gram is not really reasonable for me
Considering carbon seat posts, handle bars, forks, wheels and so on
My fattie is for gnarly off-roading. The extra weight keeps me in check while bounding over rocks, going through sand, snow and deep water. I don't do too much uphill with it.
Cheers
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#24
Senior Member
bummer on the leak, light tubes for trails are never the answer, I usually just save them for backups. I'd just stick with a regular tube till you replace the rim. Fat tires unlike smaller tires are less forgiving to rim damage. Also consider a few more PSI with tubes to avoid pinch flats. I was getting them every other ride till i got tired of it and stuck with around 10 pounds in the rear. Yes, it bounces around, but at least I'm not patching it every week. Another route maybe to go with the smaller JJs, with less sidewall mush, you should have more stability despite the lower pressures.
Whether runnin' tubeless or tubed, have you considered supplementing w/ some Stan's? (2750 miles/GDMBR while running tubeless w/ WTB Rangers ALL of the punctures, including the ones suffered w/ the NM goat head thorns sealed w/Stan's).