"raising the bar" on V20c

Henri

scatter brain
I have changed to the longest chainstays and like the new hight of the bottom bracket, but it is so high, the handle bar slider is about horizontal now, so that the handle bars come very low and just about touch my belly, when I'm on. It's in my way, when I want to lean forward to see or when getting on and off the seat. (I might also sit a bit higher due to a changed seat.)
On the previous model the curved slider could be installed in an upward position, to raise the bars, but my understandind is that on the V20C the slider can not be turned and can only lower the bars. Or is there an upwards curved slider available as a separate part?
I thought about turning the whole thing from the bottom bracket to the handle bars. It has a curve in the bottom area. I estimate I would need to remove some material from where the derailleur stalk is mounted, that would be okay, if I loose the ability for front derailleur, but structural integrity is otherwise sound. Would it be a problem to turn around the bottom bracket? Is it screwed in so I would reverse threads and risk it loosening over time or is it clamped and I can turn it back around inside the bike?
I could raise the bars themselves with a riser, but the slider would still poke at its current position.
I want to change the cranks soon. Will it help to use shortest possible cranks? Bottom bracket would move a fit further and come down a bit again and my legs would not come as far back anymore in the pedaling motion, so I could push the bars a bit further again.
Or could I change something in the pivot clamp area? Maybe a custom longer clamp to raise the slider. Maybe a steerer extender? (probaly too much) Or can Cruzbike provide a fork that is not cut as short, so I can put a spacer under the clamp?


(Report and better pictures about the whole built later. Ignore the mess for now. :D )
 

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cruzKurt

Well-Known Member
Not an answer to your question, but i have an extended chainstay on my bike, but the handlebars are a bit higher than yours. Maybe try the chainstay that is just a bit shorter.IMG_1753.JPEG
 

LarryOz

Cruzeum Curator & Sigma Wrangler
I have changed to the longest chainstays and like the new hight of the bottom bracket, but it is so high, the handle bar slider is about horizontal now, so that the handle bars come very low and just about touch my belly, when I'm on. It's in my way, when I want to lean forward to see or when getting on and off the seat. (I might also sit a bit higher due to a changed seat.)
On the previous model the curved slider could be installed in an upward position, to raise the bars, but my understandind is that on the V20C the slider can not be turned and can only lower the bars. Or is there an upwards curved slider available as a separate part?
I thought about turning the whole thing from the bottom bracket to the handle bars. It has a curve in the bottom area. I estimate I would need to remove some material from where the derailleur stalk is mounted, that would be okay, if I loose the ability for front derailleur, but structural integrity is otherwise sound. Would it be a problem to turn around the bottom bracket? Is it screwed in so I would reverse threads and risk it loosening over time or is it clamped and I can turn it back around inside the bike?
I could raise the bars themselves with a riser, but the slider would still poke at its current position.
I want to change the cranks soon. Will it help to use shortest possible cranks? Bottom bracket would move a fit further and come down a bit again and my legs would not come as far back anymore in the pedaling motion, so I could push the bars a bit further again.
Or could I change something in the pivot clamp area? Maybe a custom longer clamp to raise the slider. Maybe a steerer extender? (probaly too much) Or can Cruzbike provide a fork that is not cut as short, so I can put a spacer under the clamp?
I'll try and knock out a few of your questions:
You cannot flip the curved slider around like you could with the V20 curved slider. It is only made to curve into your body
I do not think you can flip the entire BB&sider assembly over and it would work, especially if any "material" needed to be removed. (@Robert Holler - can probably answer this better) - but I would definitely would not advise any modification to any CF part.
There is no way to put a riser in the "fork/slider" area (like the V20), as the fork comes pre cut and the "stack" that the slider bolts to is a "one-size fits all" component
Shorter cranks are probably a good idea as most people find that 20-30mm shorter cranks than they were used to on an upright are better. However, shortening the cranks will require you to probably move the BB closer to you which based on your long chainstay position may actually cause the BB to get higher, and therefore your handlebars to get even lower.
BUT.... if swapped the longer chainstay back for the original one - then added shorter cranks, this may be a better configuration for you.
Also - I am not sure if there is another chainstay avialable that is between the original one and the longer one. My understanding is that there are 3 different V20C CF-chainstays lengths available: (1) the stock one is the "medium" one, (2) then the long one is really long, and there is (3) one that is shorter than stock - (@Robert Holler - can also confirm or correct this)
Your suggestions about pivot clamp, longer custom clamp, or steering extender (which I am having trouble visualizing) would in my opinion be extremely hard custom parts to fabricate. When the front end was all steel it was much easier to play around making other parts, but the world of Carbon Fiber mods and custom parts raises the risk into areas that most people would not dare travel. (I think you woild have better luck offering to Crubbike to sponsor a new chainstay length between the stock and the long)
I am pretty sure V20C forks are also a single length top tube premade durng manufacturing.

Other ideas: rotate your handlebars up, or use a set of bullhorn handlbars.
...
That was a lot of stuff- to summarize what I think is the most probable for you:
Use the stock chainstay, and have some short cranks made (about 30mm shorter than what you are using)
 

ratz

Wielder of the Rubber Mallet
Other ideas: rotate your handlebars up, or use a set of bullhorn handlbars.
To my eye the entire boom is simply biased too far back. push the whole boom assembly 1-1.5 inches forward and it should pivot up to a more stable. position. With that much leverage being that far back; steering is going to be really twitchy.
 

Andreas

Member
However, shortening the cranks will require you to probably move the BB closer to you which based on your long chainstay position may actually cause the BB to get higher, and therefore your handlebars to get even lower.
I still think it's the other way around. If you keep the farthest pedal position, the BB moves forward.

Are you sure you've found the final pedal position?
I've learned that with a MBB, the "corect" pedal position has a much broader range than I initially thought.
The initial position where I felt comfortable on the first meters with the V20, I later shifted it 4 cm forward.
The switch to the long chainstay probably led you to set a conservative pedal distance again (like I did in the beginning).
However, it doesn't cost anything to test by moving the BB forward as much as you can comfortably pedal.
But with this steep angle of the chainstay, in my opinion, the effect is minimal and you only gain millimeters at the handlebars.
 

Beano

Well-Known Member
I would like at changing the bar to a wider more flared option.

A separate note why the bb so high? There comes a point where your knees will line up with your head and thus increasing your cda.
 

Henri

scatter brain
However, shortening the cranks will require you to probably move the BB closer to you
I still think it's the other way around. If you keep the farthest pedal position, the BB moves forward.
I am pretty sure, as Andreas said already, that you keep maximum leg extension the same and increse minimum leg extension. You would thereby increse the distance of the BB.

I am not sure if there is another chainstay avialable that is between the original one and the longer one.
Yes, there are multiple ones. I chose the longest, where I am at the edge of recommend body hight. I do like the hight of the BB and would like to not set it lower again and to not spend the money on another chainstay. I think the issue is not big enough, that I would do it, but it is if course on the table as last option. Had I known / thought of the issue before purchase, I might have chosen one size down.

or steering extender (which I am having trouble visualizing)
Something like this would just be an extension of the fork tube. I found a German listing that seemingly offerts 20mm rise. With the ratios present the handlebars would raise less than that, maybe about 15mm? Actually not too extreme. I might actually try something like that! (But cranks first, as I want to get new ones anyways.)
And something like this could be used to push in the slider a bit and take the place of the last centimeters of slider extension. It could then be angled up. The achievable effect would be limited and it would increase width between my legs a bit.

Other ideas: rotate your handlebars up, or use a set of bullhorn handlbars
That would only change my hand position. Problem is purely in my belly area. I might only look at changing the handlebar again, when everything else is final.

I've learned that with a MBB, the "corect" pedal position has a much broader range than I initially thought.
The initial position where I felt comfortable on the first meters with the V20, I later shifted it 4 cm forward
Interesting! I shall feel into that on my next ride!

However, it doesn't cost anything to test by moving the BB
Well it does mean some hassle with all the things that have to be loosened and tightened to spec again and trying to put the handlebars in the right llace without moving the BB again. Especially with the tight clearance I have between thighs and belly now.
But in money terms it's free, yes. :D

But with this steep angle of the chainstay, in my opinion, the effect is minimal and you only gain millimeters at the handlebars.
I'd say hight change of the bars will be more than half of distance change of the BB and also distance of bars can be changed with it for more effect. So if there is possibility to move BB, it would help, I think.

I would like at changing the bar to a wider more flared option
Those MTB bars are already plenty wide and flared! They could only use some more of what is originally drop and becomes reach on the V20. Does not change anything about the part in the middle, though, where I have the issue. ;)

A separate note why the bb so high? There comes a point where your knees will line up with your head and thus increasing your cda
I like it for pedaling. And I have not looked at it after changing it, but I did at least not notice my knees infront of my eyes while riding (have a seat with curved up shoulders) and the feet still come to around butt hight at the bottom I think. I should look into both of that, though. Shorter cranks would also reduce the range my feet and legs move up and down, keeping them more inside the frontal area of the body.
 
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