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  1. #1
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    Speedster vs Carrera

    Brief background: My wife and I have ridden our 1980's Burley Bossa Nova tandem for over 15 years, off and on. Having recently upgraded our road bikes (after 20 years on the last one) I really appreciate the jump in technology in improving the overall ride experience. The Burley is a slow handling bike and laborious to get going. So we have decided to upgrade our tandem with the intent of doing 50-80 mile rides with occasional 2-3 day trips with light packing of clothes only. We are a 370 lb team which I feel factors into our decision.
    We have test ridden several tandems and have narrowed it down to a Co-motion Speedster or Carrera. The Speedster and Carrera were both significant improvements to our current tandem and very enjoyable to ride. My quandary is that I prefer the Carrera and felt that it handled better and accelerated better, but I don't know if I'm just convincing myself of that or there is an actual noticeable difference. The Carrera has a carbon fork, timing belt, Rolf wheels and a lighter frame compared to the Speedster. Both were using the same tire inflated to the same pressure. The analytical side would say that those options would not provide an appreciable difference in acceleration but handling might feel different based on the fork and wheels. My gut says get the Carrera but my brain says stick with the Speedster - mostly for the durability factor. The cost difference is not a factor for us between the two bikes.
    Would you expect there to really be a noticeable difference or am I just imagining it?

  2. #2
    Senior Member Paul J's Avatar
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    dvdt, I'm not sure if you are looking at a Speedster in stock somewhere or if it will be ordered. Within the past month Co-Motion has changed the design of the Speedster which removes the Lateral Tube so it might be more in line with the Carrera. Don't know if this is a help or not, you might already know this so it is old news. Either way you'll have a great bike!
    1982 Merckx Campy Super Record, 1995 Merckx Campy Centaur 10, Bushnell Tandem, SOMA Double Cross

  3. #3
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    Yes, we test rode a 2014 Carrera and a 2015 Speedster - same overall frame design, but lighter tubing on the Carrera. Part of the benefit of being in Oregon was going down to the factory for a tour and test ride. Not many times can you meet the people that build what you buy!

  4. #4
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    The factory visit and tour is a fabulous experience. And very cool that they actually had examples you could ride, when we were there the pickings were a bit slim. You must have lucked out and they still had all the new web site bikes!

    I hate Co-Motion's new web site!

    The specs on the Speedster are inconsistent saying Reynolds 631 steel in one place and Cro-moly steel in another. Looking at the frame I tend towards the Cro-moly as it looks just like the Primera frame (which is what I have) albeit with upgraded components. Basic straight steerer tube. The specs call for wider 35C tires. Looks to be their top touring tandem. Likely close to bullet proof.

    The Carrera adds Reynolds 631, a tapered steerer tube, and carbon fork. Plus the bling wheels and Gates carbon timing belt.

    Yeah I would anticipate a difference in ride between these two. If you put a stop watch to it there is likely little difference. But we do not ride by the stop watch, we ride by what we feel. And that is going to be influenced by the cool factor. I started with a Primera Co-Pilot to manage cost. It now has Rolf wheels and Gates carbon timing belt. I probably should have just bought the cool stuff to begin with. If your heart says Carrera I would run with it. It is unlikely you will ever regret having more. You can do credit card touring just fine. If you get closer to loaded touring, you can easily swap some more basic wheels onto it for the trip.

    Personally my heart says Robusta for fun versatile riding without a Co-Pilot option

  5. #5
    WPH
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    Carrera! That nicer stuff is unlikely to break, and as vroom says you can always put some donkey wheels on for the transam tour.

    My sense is that the new Speedster without the lateral will be very good, interesting to hear what teams are saying in a year or two about actual real-world performance, given that these bikes tend to be used for touring etc.

    I outlined a plan this morning to Mrs WPH that we win the lotto and go to the factory and order a new bike. Her job is to win the lotto, I undertook to arrange the rest.

    I also agree with vroom that the new Co-motion website sux! The old one had logical equipment categories and easy navigation. The new one has me baffled.

  6. #6
    just another gosling Carbonfiberboy's Avatar
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    We have a 2003 Speedster with a WoundUp carbon fork. I really like a carbon fork. Our Speedster for sure has the Reynolds tubing. It is odd that they have different specs in different places for the new Speedster. A call or email would straighten that out. If the new Speedster is really CroMo, what does that do to frame stiffness? I wouldn't want to tour on a tandem that was less stiff than our Speedster.

    With the Carrera, you'd want a different touring wheelset, but I think every tandem that's used a lot should have 2 wheelsets, since you can't just grab a different wheel off one of your singles. Of course the carbon fork precludes front panniers, but we tour with only rear panniers when fully loaded for camp-touring as we also have a carbon fork. Handling can be a little weird with only rear panniers, but we prefer it anyway because of the lighter weight.

    We've toured with 28mm tires and an all-up weight of ~390 lbs. but I don't think I'd be happy with those tires and much more because we were out of room to increase pressure.

    Many teams have had failures with Rolf tandem wheels. I don't know if these are different from the ones that caused the problems, primarily cracked rims. Your team weight might make the Rolfs a not every day wheelset. The Rolfs have an internal width of 17mm, so I don't know how they'd handle with a much wider tire. You'd want to check on max tire size with the CoMo carbon fork.

    I've run both timing chains and Gates belt. IME there's not much to choose, really. I like the belt for touring because we're only dirty on one side, so easier to manage in hotels, etc. If it went out, it's easy to replace with rings and chain.

  7. #7
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    Our Carrera is wonderful. It is easy to lift to a roof rack, it's gates drive is silent and easy to adjust and grease free, the carbon fork has two eyelets for a front rack, and we have had zero issues with the wheelset running 28 mm gator skins other than needing a minor trying om the front wheel after hitting hole at 30 mph. The steering is responsive and predictable. I say it is a no brainier if price is no object. Go for the Carrera.

  8. #8
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    Co-motion told us that the Speedster and Carrera are both Reynolds 631, just the wall thickness and butting are different to lighten the Carrera. They are really trying to put the Speedster in the touring category and performance upgrades are no longer provided. The carbon fork is probably my most desired upgrade and from what I understand, does not fit the 2015 Speedster frame anymore. The test ride of the Speedster really felt damped on the front end even though the steering dynamics seemed similar. Everything is high performance compared to our very sedate and ponderous Burley.
    We will definitely only do credit card touring - that's what the stoker says. We don't even camp on the ground anymore!
    And Co-motion told us they are working on cleaning up and adding to their website. I asked specifically about the gallery they used to have of all the fantastic paint jobs.

  9. #9
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    Quote Originally Posted by Carbonfiberboy View Post
    We have a 2003 Speedster with a WoundUp carbon fork. I really like a carbon fork. Our Speedster for sure has the Reynolds tubing. It is odd that they have different specs in different places for the new Speedster. A call or email would straighten that out. If the new Speedster is really CroMo, what does that do to frame stiffness? I wouldn't want to tour on a tandem that was less stiff than our Speedster.

    With the Carrera, you'd want a different touring wheelset, but I think every tandem that's used a lot should have 2 wheelsets, since you can't just grab a different wheel off one of your singles. Of course the carbon fork precludes front panniers, but we tour with only rear panniers when fully loaded for camp-touring as we also have a carbon fork. Handling can be a little weird with only rear panniers, but we prefer it anyway because of the lighter weight.

    We've toured with 28mm tires and an all-up weight of ~390 lbs. but I don't think I'd be happy with those tires and much more because we were out of room to increase pressure.

    Many teams have had failures with Rolf tandem wheels. I don't know if these are different from the ones that caused the problems, primarily cracked rims. Your team weight might make the Rolfs a not every day wheelset. The Rolfs have an internal width of 17mm, so I don't know how they'd handle with a much wider tire. You'd want to check on max tire size with the CoMo carbon fork.

    I've run both timing chains and Gates belt. IME there's not much to choose, really. I like the belt for touring because we're only dirty on one side, so easier to manage in hotels, etc. If it went out, it's easy to replace with rings and chain.
    We have a similar set up: '04 Speedster & a Wound-up fork. We are very pleased with THE BOAT. As an aside, we're a 320 lb team and we don't tour. I readily agree that if you go the Carerra, do pick up a new set of rims for your daily rides, and use the Rolfs for specialized stuff like rallyes. Our LBS owner strongly feels that radial spoked rims aren't a good daily option, especially with high tension spokes. We are getting ready to pull our Spinergy rims off for the winter and return to the original Velocity Dyads, partly for training purposes and partly to give the Spinergys a rest.

    While it's always easier to spend other people's money, I'd probably go with the higher content. Piece meal upgrades will probably cost you more in the long run. It's not likely that there will be any light-year advances in tandems & components in the near future.
    Jeff

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  10. #10
    just another gosling Carbonfiberboy's Avatar
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    We're running Kinlin 279/BHS C472w rims, which come in 36H drilling. I think these are superior to the Dyads for a wide rim. We're running them on Chis King hubs with CX-Ray spokes. Durable fast wheels, best I've ever owned. Since you'll have discs, you should probably go with a stronger spoke. Twocicle says DT Aero Comp in cross-3.

  11. #11
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    Quote Originally Posted by Sprout97 View Post
    ...I readily agree that if you go the Carerra, do pick up a new set of rims for your daily rides, and use the Rolfs for specialized stuff like rallyes. Our LBS owner strongly feels that radial spoked rims aren't a good daily option, especially with high tension spokes. ...
    First note that all of the Co-Motions now run disc brakes thus radial spoke options no longer apply (and in absence of rim/hub torque loads work just the same as crossed).

    Next run 'em if you got 'em. This idea of saving wheels for special occasions because they might break is perverse logic. If I am going to have a breakdown of any sort I would much rather have it on a "daily ride" where I am likely closer to home with less of an audience and not time pressured. On a longer or organized ride is when I want the bike to be the least of my worries. I run the Rolfs all the time and plan to keep doing so and expect no trouble from doing so. I find the internet really distorts some of these situations by providing anecdotal evidence of point failures without the balance of non-failure data. Everything has a failure rate but the way we report our problems gives one an impression of the failure rate being much higher than it really is.

    The way I look at it is Rolf builds these wheels FOR tandem use and has done so for long enough to have experience with the design and application. The same for Co-Motion. That means we are not looking at an early adoption of new technology. We are looking at companies that continue to sell a product, suggesting the failure rate is acceptably low.

    My original comment was to swap for loaded touring where the extra weight carried and distance from help warrant added design margin.

  12. #12
    Clipless in Coeur d'Alene twocicle's Avatar
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    Quote Originally Posted by Sprout97 View Post
    We have a similar set up: '04 Speedster & a Wound-up fork. We are very pleased with THE BOAT. As an aside, we're a 320 lb team and we don't tour. I readily agree that if you go the Carerra, do pick up a new set of rims for your daily rides, and use the Rolfs for specialized stuff like rallyes. Our LBS owner strongly feels that radial spoked rims aren't a good daily option, especially with high tension spokes. We are getting ready to pull our Spinergy rims off for the winter and return to the original Velocity Dyads, partly for training purposes and partly to give the Spinergys a rest.
    While radial lacing is the stiffest pattern, it is not the strongest. Plus it puts a lot of stress through to the hub, usually causing flange failures when failures occur, plus cracking rims, etc. Those problems can be mitigated by using a cross-x pattern. For our front BHS/Kinlin 32h rimmed wheel / rim brake setup, I had that built with cross-2... a little stiffer than x3 and resulted in better bracing angles. For disc brake setups, x3 (typical) or more is required.

    Quote Originally Posted by Carbonfiberboy View Post
    We're running Kinlin 279/BHS C472w rims, which come in 36H drilling. I think these are superior to the Dyads for a wide rim. We're running them on Chis King hubs with CX-Ray spokes. Durable fast wheels, best I've ever owned. Since you'll have discs, you should probably go with a stronger spoke. Twocicle says DT Aero Comp in cross-3.
    This rim does seem to be holding up exceptionally well. For teams over ~320lbs wanting to build up appropriately strong but lighter weight wheels, I would forgo trying to use aero spokes at all and stick with high quality DB round spokes instead such as Sapim Race or DT Comp. A round spoke provides more lateral stiffness to the wheel. Even at a light weight team of 250lbs (95lb stoker helps to hit that target), I can feel our rear wheel (32h 135mm w/DT Aero Comp) give a little sideways under certain higher side load circumstances.

  13. #13
    just another gosling Carbonfiberboy's Avatar
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    Quote Originally Posted by twocicle View Post
    <snip>
    This rim does seem to be holding up exceptionally well. For teams over ~320lbs wanting to build up appropriately strong but lighter weight wheels, I would forgo trying to use aero spokes at all and stick with high quality DB round spokes instead such as Sapim Race or DT Comp. A round spoke provides more lateral stiffness to the wheel. Even at a light weight team of 250lbs (95lb stoker helps to hit that target), I can feel our rear wheel (32h 135mm w/DT Aero Comp) give a little sideways under certain higher side load circumstances.
    Since all spokes are always under high tension in a properly built wheel, I don't see how a round spoke will make a stiffer wheel than a bladed spoke of the same gauge. I have never felt any lateral wheel flex on any bike including our tandem with 135 lb stoker, no matter how hard we corner or hammer standing. What with tire roll and frame flex, I don't see how one could sort out wheel flex. I have felt serious frame flex when standing with a touring load, but don't feel it when sport riding. I have the stock 145mm CoMo rear spacing and an almost symmetrical rear hub.

    Stiff wheels are often mentioned with approval. However, it should be noted that a bicycle wheel is so rigid that its elasticity is not discernible because the tires, handlebar stem, frame, and saddle have a much greater combined elasticity. Therefore the differences among well constructed wheels are imperceptible to a rider.
    http://poehali.net/attach/Bicycle_Wh...bst_Brandt.pdf

  14. #14
    Clipless in Coeur d'Alene twocicle's Avatar
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    I can only relate my perception of this occurring in certain conditions only, where speed and handling aggressiveness is likely quite different than yours, so your experiences may vary.

    Regarding wheel building:

    Since all spokes are always under high tension in a properly built wheel,
    That statement is very much false for metal spokes. Under load, spoke tensions can vary by quite a lot during a duty cycle. Spinergy BPO spokes are something of an exception as they are much more elastic and result in a more uniform tension throughout the wheel during a duty cycle (ignoring other BPO characteristics in this discussion).

    To support your argument regarding aero spokes, you would have to believe that spoke gauge plays no part in a wheel's lateral strength. In many cases with an aero spoke, you are looking a sub 1mm thickness vs. 2.3mm in the fore/aft profile. This is done by taking a round 15 gauge DB section and flattening it. However, flattening an aero spoke profile does indeed influence its side-load characteristics and can be simply demonstrated by bending an aero spoke fore/aft, then sideways... there is a substantial difference in stiffness between these to planes whereas a round spoke is obviously going to have symmetrical characteristics. Putting a spoke under tension does not increase its inherent lateral strength.
    Last edited by twocicle; 10-23-14 at 01:58 PM.

  15. #15
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    Last edited by fietsbob; 10-23-14 at 01:23 PM.

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    Quote Originally Posted by fietsbob View Post
    These both Porche models?
    Porsche will get miffed if they decide to make bikes as Mercedes.

  17. #17
    Senior Member Team Fab's Avatar
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    Quote Originally Posted by twocicle View Post
    I can only relate my perception of this occurring in certain conditions only. Our speed and handling aggressiveness is likely quite different than yours, so your experiences may vary.

    Regarding wheel building:

    To support your argument you would have to believe that spoke gauge plays no part in a wheel's lateral strength. However, a flattened aero spoke profile does indeed influence its side-load characteristics and can be simply demonstrated by bending an aero spoke fore/aft, then sideways... there is a substantial difference in stiffness between these to planes. In many cases with an aero spoke, you are looking a sub 1mm thickness vs. 2.3mm in the fore/aft profile. This is done by taking a round 15 gauge DB section and flattening it. Putting a spoke under tension does not increase its inherent lateral strength.



    That statement is very much false for metal spokes. Under load, spoke tensions can vary by quite a lot during a duty cycle. Spinergy BPO spokes are something of an exception as they are much more elastic and result in a more uniform tension throughout the wheel during a duty cycle (ignoring other BPO characteristics in this discussion).
    I would like to state right from the start that I am not a wheel builder at all. But I am not sure I agree with what you say.

    You could lace a wheel with string. Which has absolutely no strength when you bend it. But if under tension would have enough strength to support the wheel.

    Alternately, one way to test your theory on the bladed spoke would be to lace a wheel with the blades at a 90 degree angel to the direction of travel and see if there is more or less lateral movement.

    However, I do believe that because spokes are used under tension, it does not matter which way they are laced. The strength of the wheel and feel of the wheel only varies with the ability of the spoke to withstand tension, and how much they actually stretch.

    Just like the string above that has no lateral strength on its own, when it is under tension it can carry incredible load. Very much like the PBO spokes.

    I think the reason that the bladed spokes feel different is because they do not have identical tension strength or stretch.

    Please correct me if I am wrong. I do not claim to have any experience in this.

  18. #18
    Clipless in Coeur d'Alene twocicle's Avatar
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    Unfortunately I do not have a stash of wheel building links available... thought I did. Was hoping to pull up the resource info for lacing patterns and spoke profile types but can't find it now. Grrr. Sort of a cop out I know. I'll keep looking.
    Last edited by twocicle; 10-23-14 at 03:21 PM.

  19. #19
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    Quote Originally Posted by bike_forever View Post
    Porsche will get miffed if they decide to make bikes as Mercedes.


    Porsche did make a carbon mtn bike back in the day...Full suspension if I remember correctly, and over half the price was the "Porsche" logos. Sure didn't ride like a Porsche drives.

  20. #20
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    Quote Originally Posted by Team Fab View Post
    I would like to state right from the start that I am not a wheel builder at all. But I am not sure I agree with what you say.

    You could lace a wheel with string. Which has absolutely no strength when you bend it. But if under tension would have enough strength to support the wheel.

    Alternately, one way to test your theory on the bladed spoke would be to lace a wheel with the blades at a 90 degree angel to the direction of travel and see if there is more or less lateral movement.

    However, I do believe that because spokes are used under tension, it does not matter which way they are laced. The strength of the wheel and feel of the wheel only varies with the ability of the spoke to withstand tension, and how much they actually stretch.

    Just like the string above that has no lateral strength on its own, when it is under tension it can carry incredible load. Very much like the PBO spokes.

    I think the reason that the bladed spokes feel different is because they do not have identical tension strength or stretch.

    Please correct me if I am wrong. I do not claim to have any experience in this.

    Hopefully someone with a real engineering background will chime in on this but my layman's understanding is that you are generally correct about the round spokes possibly having more tension strength and therefore making stiffer wheel.

    I think that lacing pattern does matter when considering the twisting motion caused by the payment under acceleration on the rear wheel or braking of a disk brake wheel. This is why you never see radial rear wheel drive side lacing. Likewise 3x would tend to resist braking force on a disk brake wheel better than a 2x lacing.

    Also the bracing angle of the spokes on a widely spaced hub would seem to allow for the same spokes to better resist side loads. Luckily road wheels have very little side loads to resist even when cornering due to the lean of the bike.

  21. #21
    just another gosling Carbonfiberboy's Avatar
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    Quote Originally Posted by twocicle View Post
    I can only relate my perception of this occurring in certain conditions only, where speed and handling aggressiveness is likely quite different than yours, so your experiences may vary.

    Regarding wheel building:



    That statement is very much false for metal spokes. Under load, spoke tensions can vary by quite a lot during a duty cycle. Spinergy BPO spokes are something of an exception as they are much more elastic and result in a more uniform tension throughout the wheel during a duty cycle (ignoring other BPO characteristics in this discussion).

    To support your argument regarding aero spokes, you would have to believe that spoke gauge plays no part in a wheel's lateral strength. In many cases with an aero spoke, you are looking a sub 1mm thickness vs. 2.3mm in the fore/aft profile. This is done by taking a round 15 gauge DB section and flattening it. However, flattening an aero spoke profile does indeed influence its side-load characteristics and can be simply demonstrated by bending an aero spoke fore/aft, then sideways... there is a substantial difference in stiffness between these to planes whereas a round spoke is obviously going to have symmetrical characteristics. Putting a spoke under tension does not increase its inherent lateral strength.
    I build all my own wheels. All spokes are elastic. The whole point of tensioning spokes to a particular kgf is to stretch them enough so that they are always under tension. It is not to stiffen the wheel, as a wheel with low spoke tension will be as stiff as one with high spoke tension. It is true that tension will vary slightly in the spokes of a loaded and rotating wheel. Complaints of broken spokes are almost always because too little spoke tension was used, thus the spoke fatigued at the elbow during its duty cycle due to loading and unloading.

    Of course spoke gauge is a factor in strength and stiffness. However gauge is gauge and has nothing to with the sectional shape. Since spokes are always in tension, their column behavior is irrelevant. The problem with trying to build a stronger/stiffer wheel by using thicker spokes is that thicker spokes don't stretch as much at the rim manufacturers recommended spoke tension. Thus, having less stretch, they will change tension more as the wheel rotates under load and fatigue earlier, thus actually creating a less durable wheel. This is the reason that 14-15 double butted spokes work just as well for 120 lb. people on singles as they do for 350 lb. tandem teams. We just use more of them for heavier loads. A single 14g spoke will have a yield strength well over 500 lbs.

    Spokes change spoke tension slightly due to the rim bending at the ground contact patch. Thus a deeper section rim will produce a more durable wheel for the same spoke count. And thus a higher spoke count limits changes in spoke tension by spreading the force changing spoke tension over more spokes.

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    Wow is this thread flying off into the weeds or what??? Mea-culpa too.

    Now perhaps we should get back to our original discussion of Co-Motion Speedster vs Carrera?

    DVDT question for you: are you going to be able to buy direct or are you going to have to work with a local dealer?

  23. #23
    Senior Member joe@vwvortex's Avatar
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    Also have an 04 Speedster with a Wound Up CF fork - but it is a disc fork now - as I upgraded a few years ago. When I purchased the bike - the Rolf wheels were a relatively inexpensive upgrade through Co-Mo so I went with a set. I've had my share of problems with spoke breakage and rims cracking and I'm on my second set as I bought a new set in 2010. After my last rim failure I purchased a set handmade of 32 spoke wheels w/ db Sapim round spokes and brass nipples laced to Kinlin 29 rims and WI6 disc hubs. They are only slightly heavier than the Rolfs and I like them SO much more. The hub to fork interface is better - as the WI6's have a larger axle caps which mate better with the fork in the front and dropouts in the rear. I'm able to run less psi in the tires - although only 5 psi less - the ride is more forgiving. Then on top of that they are stiffer laterally when climbing out of the saddle. Lastly - if a rim does crack - I don't have to send the hub back to Rolf and have them replace the spokes, nipples and rim at a cost of more than the new wheel would cost me to build.
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  24. #24
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    I have an option of buying direct or through a dealer. The dealer is an hour north, Co-motion is an hour south. But I don't get the impression that it matters, the ability to upgrade the Speedster does not appear to be an option relative to fork, wheels, timing belt - they direct you to the Carrera if you want to do that. Or I would lose the cost benefits of buying a package.
    I knew the wheels would be the most contentious issue and it is for myself as well. My inclination was to go with the Carrera, run the Rolfs and if I have problems, purchase a set of more durable wheels. Co-motion and Rolf both insist that their wheels are meant for tandem use and yes, you might see some shorter life as you do with most performance upgrades. Also, some unknown percentage of users have experienced problems with Rolfs. There is probably an optimum wheelset that can be built between the Rolfs and the Speedster wheels. When I upgraded my road bike after 20 years, I truly believe the wheels were the biggest improvement I got.
    I prefer the carbon fork, neutral on the timing belt and torn on the wheels.

    My original question is really would one expect to notice a difference between the two bikes or is the difference so small, it's lost in the noise and one's perception? Why did the Carrera feel more lively?

    Thanks for all the responses, they help.
    Last edited by dvdt; 10-23-14 at 06:34 PM. Reason: spelling

  25. #25
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    Sounds like you are around the Corvallis area.

    The timing belt does the following in order of probable practical value:

    1. Eliminates a source of grease and dirt when handling the bike or accidentally bumping against it.
    2. Reduces or eliminates timing chain maintenance and wear.
    3. Reduces weight (the timing rings may be heavier than chainrings but the belt is MUCH lighter than the chain).
    4. Eliminates any chain noise from the front of the bike, runs silently.
    5. Is eye catching and looks really cool. We get more comments on the carbon belt.

    I would get a belt.

    As I recall Co-Motion claims 2.75 lbs reduction for their performance kit: CF fork, Rolf wheels, and carbon belt. Drop a couple more pounds in the frame...
    I suspect the Speedster is a 35-40 lbs bike.
    I am guessing the Carrera is a 30-35 lbs bike.
    Yes you can and will notice 5 lbs dropped from the bike.

    One last thought: since you only live an hour away from Rolf warranty or repair service is much less hassle for you than somebody across the country. Just sayin'

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