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1 bike per day + 1 or 2
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Discussion Starter · #1 ·
Here is the first picture of the Pedal Force MT Single Speed build up that I finished this morning. I hope to get out and ride it today when my wife gets home from work. Should be a lot of fun.

As it sits in the picture, it is at exactly 15 lbs. Once I get the chainring situation dealt with and maybe the Trigon forks, it should be closer to 14.5 lbs. or a bit less.




 

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Recovering couch patato
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Wow! That's light!

What about cork or foam grips to lose another 50g?
That tensioner looks scary to me, and over 100g? A Rennen Rollenlanger is more bomproof and lighter. And there's cheap rip-offs.
 

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Discussion Starter · #3 ·
Foam grips that I have in the garage are very light but only save 28g over these. These are pretty light for rubber. If I do anything, I will go back to using bar tape on the bars. It will only weigh about 10g for the bar tape.

As for the tensioner, Surly is one of the best in my opinion. It works flawlessly and runs very smoothly. Ya a bit on the heavy side really at 15 lbs. and most likely close to 14 lbs with new forks and a carbon spiderless chainring, I am not going to worry to much about anything else.
 

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Very nice! Vuelta brakes look great and it's nice to see that frame has plenty of tire clearance.

Why do you want to change your chainring?

Do you have an accurate way to measure head angle? I think lots of us are worried about geometry with rigid or low-profile forks. If you could post head angle and fork length, that would be great.

If I may offer some suggestions:

1. Lose the chain tensioner.
It looks heavy and ugly on such a minimalist bike. You may get lucky and only need to shorten the chain. If that doesn't work, you could use a half link. There are lots of tricks singlespeed guys use to get chain length without tensioners. If you lose the Surly tensioner, you could also remove or cut down the derailleur hanger. Spare hangers are available from Pedal Force, so hacking one is no big deal.

2. Remove the extra cable stops.
You can easily drill out the heads of the rivets and remove the extra stops. This saves weight and cleans up the look. If you need to add them later, you can easily pop-rivet them back on. If you don't remove them, at least paint the ugly rivets black.

3. Cut off the disk brake mount?
You could save an ounce or two by removing the disk brake tabs. If that dropout is easily replaceable and available from Pedal Force, it seems like a no-brainer. However, if it's a permanent mod, that's a tough call.

4. Flat bar!
You already know this, but I'll be pest and remind you that flat bars are lighter. I'm a geek, so I still prefer longer steerer and/or high-rise stem over a riser bar.
 

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1 bike per day + 1 or 2
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Discussion Starter · #5 ·
EuroMack,

Thanks for the suggestions. All good but I think I will stick to where the bike is now.

I have thought about going with a flat bar but I had this in the garage on my last build and do not really want to get a new one as this seems to work for now ;)

The chain tensioner is only 108g so not that heavy at all but yes it is additional weight. So it will stay and as mentioned before, works amazingly good and keeps the chain in place. I am using a 16t sprocket off my old Ultegra cassette so that has worked a lot better than the one in the picture.

The chain will be changed from a Sram hollow pin to a KMS X10SL that I have and this will further reduce some weight.

As for the chainring, I hate the way that it looks, I hate using the standard chainring with the outer part of the spider showing and it having the washers to get the chainring bolts to work. I could use shorter ones or get the guys at work to machine then down but it still looks like crap.

I will be getting a custom carbon spiderless chainring built soon. I am just working on the details right now with a company that can do this for me.

I will most likely be changing the BB from the FSA Platinum Ti that I am using now (185g) to the KULT BB (142g) that I have on my road bikes. They are all 68 X 108 and I will just go buy some new lighter BB for the road bikes.

As for any modifications to the frame it self, there is no way that I will touch the frame. It will stay as I bought it.

With the change to the Trigon fork (I am still going to most likely do this) and the carbon chainring as well as a new BB, the bike should be around 14 lbs which for the most part is stupid light already. Yes I could go lighter but the bike being between 14 and 15 pounds is where I would like it to stay. The bike is just a fooling around, ride with my son (when he learns to ride) or go riding with the wife. When I ride with her, I always take the SS and that way, it is a bit of work to keep up with her and makes it a bit more even fun time for us.
 

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i don't give a shift
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I use these type of tensioner too. They do work well and have tuning potential if you want to save weight. Here's what you can do:

- aluminum pivot bolt
- aluminum clamp bolt
- replace the steel rod that holds the pulley with aluminum, hollow Ti or carbon rod
- replace those two alu disks on the outside of pulley with carbon ones
 

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Did you consider a set of these...

I really like the look of the frame and some of the parts you have. It's kind of a shame that it will only be used for touring with the family with such a nice bike :mad:

Did you consider these middleburn Rs-8 cranks? They are pretty light and the spiderless ring would be just what you are looking for.
 

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Discussion Starter · #9 ·
I did consider a few other crank sets but for the most part I already had this crank and I wanted to stay with carbon. I am not just sorting out a custom made carbon spiderless chainring for the build. Should be very cool.
 

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I used to run singlespeed to avoid boredom when riding with the girlfriend, so I understand the design goals! In a similar fashion, I've also learned to play billiards left-handed...

I had the same aesthetics concern when I converted my triple crank. My quick solution was to move the 32t chainring to the outer position. Could you do this?

How does the spider attach to the crank? Perhaps you could adapt one of these:
http://www.global-flat.com/parts/Sprockets/group/14

I'm looking at this one because it's made in Rochester NY (home of my alma mater) by the drummer from Stryper. I never liked Stryper, but I think it's cool that a rock star is now machining BMX parts:
http://www.global-flat.com/parts/part/400

It's your bike, but I'm still going to beat you up for running 110g tensioner that may not be needed!
Have you tried to bypass the tensioner and just shorten the chain? You may get lucky and not need tensioner, especially if you're willing to use a half-link. Here's a nice article from Sheldon Brown:
http://sheldonbrown.com/singlespeed.html

And here's a calculator to find combos that may work without tensioner:
http://www.peak.org/~fixin/personal/fmu/php/formfmu.php

According to PedalForce, the frames all have 420mm chainstays, except the 21in size has 425mm.
 

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1 bike per day + 1 or 2
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Discussion Starter · #11 ·
EuroMack,

That is fine with the beating up about the chain tensioner. I might go with a Paul's Melvin and tune it down from 76g with some TI bolts and maybe some Carbon Pulley's. I will still take a beating but it will be a lot lighter.

You can still beat me up but until I see a sub 15 lbs. SS MTB in your hands I will just take it with a grain of salt. ;)
 

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Discussion Starter · #12 ·
The carbon spiderless chainring is in the works as we speak so that will be pretty cool.

Also like collideous has mentioned, there is a lot of room for tuning still on the Singulator or if I get the Paul's Melvin, there is tuning available and most likely a 50g tensioner.
 

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Ack! Tuned Melvin is even worse because it's extra weight AND extra money! If you tell me you at least TRIED to run without tensioner, then I'll quit harassing you...

What rear hub is that? You could possibly use an eccentric axle from Fixed Innovations or someone else to adjust tensions without extra parts.

Regarding my 15lb SS MTB: I already threw down the gauntlet with my 12lb singlespeed hardtail in this thread: :p
http://forums.mtbr.com/showthread.php?t=300292

If customs weasels cooperate, I should have my PedalForce plastic frame this week. But, I'm starting at a disadvantage because mine is adult-size ;)

Ty,
They're $850 from PedalForce.com , but several guys were looking to sell them around the $530 group buy price. I think there were a few 21's up for grabs. What size do you need?

http://classifieds.mtbr.com/showproduct.php?product=6152&cat=7
 

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Discussion Starter · #15 ·
Euromack,

The hubs are Hugi rebadged as Specialized. The whole wheel set is 1450g with rim tape so pretty light and to be honest I have beat the crap out of these and have never trued them ever. They are solid so I will stick with them until they die.

I did try the chain today with another one that I had laying around. I can get the chain pretty tight but I still do not like the fact that it is a bit loose. If I really torque the chain it will slip. I think I will stick with the chain tensioner even thou everyone seems to hate it.

So on that note, what is the lightest chain tensioner out there. Paul's claims theirs is 76g which is pretty light compared to the 108g Surly.

I am pretty sure that I could run the Paul's and replace the stock pulley's with KCNC or Carbon and get the weight down more.
 

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Hack Racer
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EuroMack said:
Ack! Tuned Melvin is even worse because it's extra weight AND extra money! If you tell me you at least TRIED to run without tensioner, then I'll quit harassing you...

What rear hub is that? You could possibly use an eccentric axle from Fixed Innovations or someone else to adjust tensions without extra parts.

Regarding my 15lb SS MTB: I already threw down the gauntlet with my 12lb singlespeed hardtail in this thread: :p
http://forums.mtbr.com/showthread.php?t=300292

If customs weasels cooperate, I should have my PedalForce plastic frame this week. But, I'm starting at a disadvantage because mine is adult-size ;)

Ty,
They're $850 from PedalForce.com , but several guys were looking to sell them around the $530 group buy price. I think there were a few 21's up for grabs. What size do you need?

http://classifieds.mtbr.com/showproduct.php?product=6152&cat=7
Maybe there will be interest in another group buy if people are happy with this last batch. I for one didn't expect the frames to turn out so nice. Else I would've jumped in too.
 

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EuroMack said:
. . . .

Ty,
They're $850 from PedalForce.com , but several guys were looking to sell them around the $530 group buy price. I think there were a few 21's up for grabs. What size do you need?
I would be looking for something like an 18".

With the current £/$ exchange rate / weak dollar - $850 is pretty cheap !
 

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Lighter tensioners

I was going to suggest mounting the Surly tensioner inboard of the derailleur hanger in order to protect it and to reduce weight. But, it appears that the combo of Surly plus those large-diameter cog spacers would interfere.

These may be a cheap, easy solution:

http://www.nashbar.com/profile.cfm?sku=14063
or
http://www.performancebike.com/shop/Profile.cfm?SKU=23062

They appear to be same parts except different cog sizes.

I don't know the weights, but I would guess them lighter than the Surly/Pyramid model.

The lower profile and smaller-diameter spacers should let you mount the tensioner INBOARD of the derailleur hanger. This allows you to cut the unused portion of the rod and reduce weight. As a bonus, you can tune your chainline with the smaller spacers. This allows you to move your 32t ring to the outside so your spider is hidden.

Then, I found this:
http://forums.mtbr.com/showthread.php?t=231146

A small aluminum chainring only weighs about an ounce and it LOOKS way cool, especially for riding with the kids. Ideally, one should use a singlspeed cog or chainring, for better engagment.
 

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Cheers! said:
maybe we should start another group buy. I'm interested and a friend here at work is too. So that could be 3 out of the 50 required?
Don't get too excited, just yet. For the moment, we only KNOW that they're light and pretty. Since nobody has complained about assembly issues, we can infer that the headset/BB finish and overall frame alignment must be OK.

At this point, I still have 2 concerns:

1. Geometry - Chainstays are very short, and head angle may be very steep with my short fork. This will be great for tight singletrack, but maybe a little hairy on fast descents. I'll see soon enough.

2. Durability- Those huge-diameter tubes must be darn thin to acheive 1200g weight. Give it a month or so and see if anyone complains of strange noises, delamination, cracks, etc.

What incentive does Pedal Force have to do another group buy? If the reviews are good, they can sell them at $850. If the reviews are bad, well then you may trouble finding 50 buyers. If you don't want to pay $850, there's always ebay. There are guys selling frames that appear identical to the Pedal Force road frames. I would guess that we'll see similar mountain frames by summer.
 
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