Newbie with build questions

[Seth Cooper]

Hi, another recumbent newbie with some questions. I'll introduce myself, I'm 45 yrs old, long time casual DF rider (about 1500 - 2000 miles a year, road, MTB, some CX, Fat tire for the snow, so I have 4 DF bikes). Back injury last summer made long DF rides a problem, so I borrowed a friends Performer, put about 500 miles on it. I didn't like the way it was hard to climb with it, and the noise the long chain line made. I just happened to meet a CruzBike owner on a multi-day ride, and took his for a spin around the parking lot, and now i am here.

Looking at buying a cruzbike. I am hoping to buy a Vendetta frame and move the SRAM eTap drivetrain over from my road bike. Four questions with this:
1. Brakes. I have rim brakes. Looks like the Vendetta can accommodate either rim or disc? I will probably switch to disc at somepoint because of safety in the rain with carbon wheels and to run more tire sizes.
2. Tire Sizes. What is widest that can be run? Could I use the front fork from the S40? What is the widest tire it can run?
3. Drivetrain. My eTap has 50-34 and a 11-28 cassette. Looks like there is a medium cage from SRAM now that can give me 11-32. The 28 was fine for the hills around me on the DF bike, but from reading the forums it sounds like I may need the 32. But other than cassette size is there anything in the group that would not work?
4. Crank Length. (related to #3). I am not sure of my crank length, but it probably is the long option. I'm 6'3". What is the benefit of shorter cranks? would I be unhappy with mine?

And one more question about seat angle. I noticed one Vendetta owner built an adjustable seat tilt for his, are there any commercially available ones? I actually like the idea of an adjustable while riding. I have a KsLev adjustable seat post for my mountain bike that I never use, so I could possibly adapt it to my seat.

Thanks in advance for any answers or advice!

Seth

 

[LarryOz]

Hi, another recumbent newbie with some questions. I'll introduce myself, I'm 45 yrs old, long time casual DF rider (about 1500 - 2000 miles a year, road, MTB, some CX, Fat tire for the snow, so I have 4 DF bikes). Back injury last summer made long DF rides a problem, so I borrowed a friends Performer, put about 500 miles on it. I didn't like the way it was hard to climb with it, and the noise the long chain line made. I just happened to meet a CruzBike owner on a multi-day ride, and took his for a spin around the parking lot, and now i am here.

Looking at buying a cruzbike. I am hoping to buy a Vendetta frame and move the SRAM eTap drivetrain over from my road bike. Four questions with this:
1. Brakes. I have rim brakes. Looks like the Vendetta can accommodate either rim or disc? I will probably switch to disc at somepoint because of safety in the rain with carbon wheels and to run more tire sizes.
2. Tire Sizes. What is widest that can be run? Could I use the front fork from the S40? What is the widest tire it can run?
3. Drivetrain. My eTap has 50-34 and a 11-28 cassette. Looks like there is a medium cage from SRAM now that can give me 11-32. The 28 was fine for the hills around me on the DF bike, but from reading the forums it sounds like I may need the 32. But other than cassette size is there anything in the group that would not work?
4. Crank Length. (related to #3). I am not sure of my crank length, but it probably is the long option. I'm 6'3". What is the benefit of shorter cranks? would I be unhappy with mine?

And one more question about seat angle. I noticed one Vendetta owner built an adjustable seat tilt for his, are there any commercially available ones? I actually like the idea of an adjustable while riding. I have a KsLev adjustable seat post for my mountain bike that I never use, so I could possibly adapt it to my seat.

Thanks in advance for any answers or advice!

Seth

Welcome to the tribe!
Answers:
#1: Yes the Vendetta can accommodate both rim and disk brakes and you are even free to mix and match. When we did RAAM last year we ran a front disk and back rim.

#2: Tires: I have ridden up to 28mm on my stock Vendetta. I am pretty sure you can use the S40 fork (but Robert may need to verify that). I know the stock S40 can take up to a 32C tire, but suspect it could go a little larger. Jim P put knobby's on his for a gravel event.

#3: Drivetrain: I use SRAM etap. Great drivetrain. Yes medium cage can go 32 and I think a large might get you 36. You should be fine with a 32. If you really need more torque, it might be cheaper to opt for a smaller "little ring".

#4 Crank length. Base on you question it appears you are asking about the chainstay length - I will address both.
Chainstay: There is a large chainstay that is 2" longer than the standard. I think with you height, you are probably on the edge. But it really depends on how long your inseam is. If you have really long legs for you height, then you may need the large chainstay. If you legs are short for your height then the standard will do fine. The thing you are looking for is to not get your feet too high. Once the boom reaches near horizontal it becomes twitchier and is usually less aero because your feet are so high. Robert at Cruzbike would be able to advise you based on your measurements.

Crank-length: This is another area that many people find they need to change. I am 5'7" and I ride with 140mm cranks. I have done 100's of hours of testing on this subject. For me personally, I shortened the cranks until my knee did not bend past 90 degrees on my back stroke. This helps me when beginning my power stroke forward. You legs also "move" less distance with shorter cranks so it is easy to spin faster. Spinning up to a high cadence is also faster. You do loose a tiny bit of leverrage, but that is what gears are for. Finding the ideal crank length requires some measuring and testing. I have found that most people prefer about 10-15mm less than what they are used to on their upright. Some people can ride the same length. Use this cranklength calculator to get an idea based on your specific leg measurements: http://www.recumbents.com/wisil/misc/crank_angle.asp

#5: adjustable seat: There have been several posts about an adjustable seat. I do not think there is anything commercially available right now. I think a good/simple design would be to incorporate a small pneumatic pump like on an office chair. If you released it with you weight off it would spring up - If you pulled the lever and leaned back, you could push it back down. Infinite adjustment. You would need a Thor seat or equivalent to make this work however, as the Cruzbike CF seat does not have ribbing down its length (so it is lighter) so cannot be self supported.

Good Luck - and have fun
Larry

 

[GetBent]

The thing you are looking for is to not get your feet too high. Once the boom reaches near horizontal it becomes twitchier and is usually less aero because your feet are so high.

Interesting- I learn so much on this forum. Is there an optimum height for the bottom bracket with respect to handling? If so, how does one get there? The way I see it is that the seat is fixed, my body length is fixed, and those two factors determine the fore/aft location of the bottom bracket, which then fixes the height. So the only way I can think of to lower the bottom bracket height is to use shorter cranks (causes the bottom bracket to move forward lowering the bottom bracket) or a shorter chain stay. Either of these would cause my handle bars to rise, which I would not like. Am I missing something here?

 

[super slim]

Welcome to the tribe!
Answers:
#1: Yes the Vendetta can accommodate both rim and disk brakes and you are even free to mix and match. When we did RAAM last year we ran a front disk and back rim.

#2: Tires: I have ridden up to 28mm on my stock Vendetta. I am pretty sure you can use the S40 fork (but Robert may need to verify that). I know the stock S40 can take up to a 32C tire, but suspect it could go a little larger. Jim P put knobby's on his for a gravel event.

#3: Drivetrain: I use SRAM etap. Great drivetrain. Yes medium cage can go 32 and I think a large might get you 36. You should be fine with a 32. If you really need more torque, it might be cheaper to opt for a smaller "little ring".

#4 Crank length. Base on you question it appears you are asking about the chainstay length - I will address both.
Chainstay: There is a large chainstay that is 2" longer than the standard. I think with you height, you are probably on the edge. But it really depends on how long your inseam is. If you have really long legs for you height, then you may need the large chainstay. If you legs are short for your height then the standard will do fine. The thing you are looking for is to not get your feet too high. Once the boom reaches near horizontal it becomes twitchier and is usually less aero because your feet are so high. Robert at Cruzbike would be able to advise you based on your measurements.

Crank-length: This is another area that many people find they need to change. I am 5'7" and I ride with 140mm cranks. I have done 100's of hours of testing on this subject. For me personally, I shortened the cranks until my knee did not bend past 90 degrees on my back stroke. This helps me when beginning my power stroke forward. You legs also "move" less distance with shorter cranks so it is easy to spin faster. Spinning up to a high cadence is also faster. You do loose a tiny bit of leverrage, but that is what gears are for. Finding the ideal crank length requires some measuring and testing. I have found that most people prefer about 10-15mm less than what they are used to on their upright. Some people can ride the same length. Use this cranklength calculator to get an idea based on your specific leg measurements: http://www.recumbents.com/wisil/misc/crank_angle.asp

#5: adjustable seat: There have been several posts about an adjustable seat. I do not think there is anything commercially available right now. I think a good/simple design would be to incorporate a small pneumatic pump like on an office chair. If you released it with you weight off it would spring up - If you pulled the lever and leaned back, you could push it back down. Infinite adjustment. You would need a Thor seat or equivalent to make this work however, as the Cruzbike CF seat does not have ribbing down its length (so it is lighter) so cannot be self supported.

Good Luck - and have fun
Larry

Larry, this was a VERY good reply with lots of info, especially about the boom when horizontal !

Another question for you!
Is there an optimum BB height above the seat base lowest position?

The S40 front fork can handle a 700c * 38, so with a 80 kg rider, the recommended tyre pressure is 50 psi for a 15% tyre deflection.

Is there any 60 mm deep carbon rims that are 35 mm wide, and if so, would the Aero drag be the same as a 65 D*28 W with a 28 mm wide tyre, at 80 psi for a 80 Kg rider?

What is the max Rear 700c tyre width on a 2018 Vendetta

 

[nobrakes]

Interesting- I learn so much on this forum. Is there an optimum height for the bottom bracket with respect to handling? If so, how does one get there? The way I see it is that the seat is fixed, my body length is fixed, and those two factors determine the fore/aft location of the bottom bracket, which then fixes the height. So the only way I can think of to lower the bottom bracket height is to use shorter cranks (causes the bottom bracket to move forward lowering the bottom bracket) or a shorter chain stay. Either of these would cause my handle bars to rise, which I would not like. Am I missing something here?

You can get different length chainstays, longer means BB lifts higher, shorter means BB drops lower for any given leg length. For reference I have XSeam 46” with standard chainstay, the BB is about 3 inches above the lowest part of the seat on my V20. I calculated that the next size chainstay would lift the BB by about 2-3 inches for my leg length.

 

[Seth Cooper]

Welcome to the tribe!

Crank-length: This is another area that many people find they need to change. I am 5'7" and I ride with 140mm cranks. I have done 100's of hours of testing on this subject. For me personally, I shortened the cranks until my knee did not bend past 90 degrees on my back stroke. This helps me when beginning my power stroke forward. You legs also "move" less distance with shorter cranks so it is easy to spin faster. Spinning up to a high cadence is also faster. You do loose a tiny bit of leverrage, but that is what gears are for. Finding the ideal crank length requires some measuring and testing. I have found that most people prefer about 10-15mm less than what they are used to on their upright. Some people can ride the same length. Use this cranklength calculator to get an idea based on your specific leg measurements

Larry

Thanks for the info Larry.

I took a few measurements, for the crank length calculator page. I came up with 46cm hip to knee, 56 cm knee to ball. So for a high BB bike like I guess the Vendetta would be, I would be recommended to get a 155-150mm crank. What crank setups work well with SRAM eTap? Is there anything that can mount my RED chainrings in 155mm?

I have not done my XSeam, but my inseam is 91cm.

Seth

 

[Jesse Groves]

Chainstay: There is a large chainstay that is 2" longer than the standard. I think with you height, you are probably on the edge. But it really depends on how long your inseam is. If you have really long legs for you height, then you may need the large chainstay. If you legs are short for your height then the standard will do fine. The thing you are looking for is to not get your feet too high. Once the boom reaches near horizontal it becomes twitchier and is usually less aero because your feet are so high. Robert at Cruzbike would be able to advise you based on your measurements.

Good Luck - and have fun
Larry

After reading this, I am wondering why Robert Holler recommended the long chainstay for me when I am only 6 ft? My x-seam is only 44. Is there a formula or something they go by based on height vs x-seam? My boom is very close to horizontal and the bike looks more aero with that setup, but you are saying that the shorter chainstay puts the body into a more aero position? When I have seen your bike in the past Larry, I seem to remember it having a very horizontal boom.

 

[super slim]

After reading this, I am wondering why Robert Holler recommended the long chainstay for me when I am only 6 ft? My x-seam is only 44. Is there a formula or something they go by based on height vs x-seam? My boom is very close to horizontal and the bike looks more aero with that setup, but you are saying that the shorter chainstay puts the body into a more aero position? When I have seen your bike in the past Larry, I seem to remember it having a very horizontal boom.

Jess what is the height of the BB above the lowest point of the seat base with cushion, as mine is 150 mm (6") on my Silvio V1.0 and S30, which is comfortable for me, but I am NOT a racer!
I have a 46.3" X seam and only 6' 1", so all legs, just like Larry at 4' 7" with a 40.5" x seam!
Everyone has a different X seam ti height ratio!

Here is a way to measure the X Seam.

 

[Jesse Groves]

Jess what is the height of the BB above the lowest point of the seat base with cushion, as mine is 150 mm (6") on my Silvio V1.0 and S30, which is comfortable for me, but I am NOT a racer!
I have a 46.3" X seam and only 6' 1", so all legs, just like Larry at 4' 7" with a 40.5" x seam!
Everyone has a different X seam ti height ratio!

Here is a way to measure the X Seam.

My BB is 8" higher than the lowest point of the seat.

 

[Markopolo]

After reading this, I am wondering why Robert Holler recommended the long chainstay for me when I am only 6 ft? My x-seam is only 44. Is there a formula or something they go by based on height vs x-seam? My boom is very close to horizontal and the bike looks more aero with that setup, but you are saying that the shorter chainstay puts the body into a more aero position? When I have seen your bike in the past Larry, I seem to remember it having a very horizontal boom.

I ordered my S40 prebuilt and was sent the shortest chainstay. I'm 6'1" with an xseam of 45" or similar, can't remember exactly. Maybe flavor of the week?

 

[Seth Cooper]

Thanks for the info Larry.

I took a few measurements, for the crank length calculator page. I came up with 46cm hip to knee, 56 cm knee to ball. So for a high BB bike like I guess the Vendetta would be, I would be recommended to get a 155-150mm crank. What crank setups work well with SRAM eTap? Is there anything that can mount my RED chainrings in 155mm?

I have not done my XSeam, but my inseam is 91cm.

Seth

Measurements for posterity:
X-Seam 47"
Torso 30"
Arm length 24"
Up clearance 25"

 

[LarryOz]

My BB is 8" higher than the lowest point of the seat.

Jesse - This matches mine, so I would say you a probably setup pretty nicely.
Your feet might be higher than mine, but with that Thor seat you have your body is probably a little higher took, so feet and shoulders probably match up nicely too.

 

[Jesse Groves]

Jesse - This matches mine, so I would say you a probably setup pretty nicely.
Your feet might be higher than mine, but with that Thor seat you have your body is probably a little higher took, so feet and shoulders probably match up nicely too.

Thanks Larry, you had me worried that I was doing it wrong. Despite horizontal boom, I haven't had any handling problems once I got used to the FWD.

 

[Seth Cooper]

So I got my V20 frame last week, put it together and started moving bits from my road bike. I found the RED front brake didn't fit well with the front fork. I put a nylon bushing in as a spacer to get the brake pads to clear the fork. Did anyone else see this problem?

 

[telephd]

Seth, I had a similar issue on my S30s. Chose a standard aluminum bushing with ridges all around on both sides. IIRC had to use 2 on one build to get brake pad holder clearance. I would imagine your nylon solution is just as good as the nylon shouldn't compress much.

 

[Seth Cooper]

thanks. Yeah the nylon was all the hardware store had, I thought it would be good to mock up the mount. If using a spacer is what is needed, then I'll probably get a metal one.

 

[Seth Cooper]

Finally got the Wifli rear and the 11-32 cassette from starbike so I finished putting it together and took it for a spin today. Going to take some time getting used to it, but I was able to do some pretty controlled figure eights and some straight riding. Felt good enough to clip in by the end.

I am going to have to figure out the handle bar position it felt like I had it a little too much extension.

I never got out of the small chainring while riding, but shifting it on the stand the etap FD did not have a problem shifting or rubbing in any gear position, so I was happy about that, even though it is 3-5mm above the ideal position.

I loved how quiet the ride was, and how tight I could turn, just liked how clean the setup is, everything right up front in a nice neat package.

 

[benphyr]

Finally got the Wifli rear and the 11-32 cassette from starbike so I finished putting it together and took it for a spin today. Going to take some time getting used to it, but I was able to do some pretty controlled figure eights and some straight riding. Felt good enough to clip in by the end. ... nice neat package

That is an awesome look. Understated, muted background really gives that brilliant blue some real pop. Looks amazing (even down to the Subaru it's mounted on!)

 

[Seth Cooper]

I finally decided to change from the 19" chainstay to a 21.5", but the factory sent me a 23" by mistake. I had mounted it before i noticed the difference, but I didn't connect the chain as I need to splice in 8". I am a little nervous with the reports people have about the increased twichyness of the longer stay, I had decided to go to the 21.5" to take it step-by-step, so now I have been thinking about whether to just try it, or send the 23" back and swap it out.

I think I will try it. My X-seam is 47", and with the new chainstay the bottom bracket is now about 29.5" above the ground, or 7.5" above the seat, so the 23" is the right size, but imagine it will be like learning to ride all over again. I was just learning to ride no-hands with the 19", but I suspect it will be a while before I can try that again. We will see...

 

[Seth Cooper]

I put in the extra chain (really working those master links) and took it for a quick spin. Felt good, not too much wobble, so I think I will keep it. I felt a little more power and less drag, so a win win there. Can't have the water bottle under that boom anymore, so will have to find a new home for it under the seat.

Another pic on my car carrier as a contrast to the one from march with the 19" stay three posts up.