How Far Can I Go

[david_kcmo]

So, I'm at a 6 on the measurement of where the handlebar stem(?) goes into the boom arm. I'm 5'10 so this seems a little much. So, I was trying to move the boom arm toward the seat. How far can I go? I don't want to use my Hulk Smash strength but it seems like I can get another inch or two which I need (no jokes here, please, although I'm teeing one up).

 

[velocio]

So, I'm at a 6 on the measurement of where the handlebar stem(?) goes into the boom arm. I'm 5'10 so this seems a little much. So, I was trying to move the boom arm toward the seat. How far can I go? I don't want to use my Hulk Smash strength but it seems like I can get another inch or two which I need (no jokes here, please, although I'm teeing one up).

David,

Thanks for the laugh, that stuck me as perfectly played! Just enough, without pushing it ... Very funny.

There are many folks here with much more experience with Cruzbike fit than I, but I have been working the fit issue on my S40 lately too. A "6"? No strength, and certainly not Hulk-level braun, is required to move the boom+slider further in or out, if all the bits that need to be loosed are loosed. When adjusting the boom+slider did you:

• Loosen wheel QR (the front one, btw)
• Loosen 4 bolts on the BB clamp
• Loosen the 1 bolt on the boom clamp
• Loosen the 1 bolt on the slider clamp (just above the headset)

I was pondering posting a similar question as yours, but my issue is the the entire scale is hidden inside the slider. How tall does one need to be to deserve the benefit of some boom markings? My chainstay measures about 17.5", which I think is the short version. I recently traded another S40 owner my long for his short, things were *much* worse in this regard prior to the swap.

-Jack K.

 

[david_kcmo]

Thank you. One question - you seem to be asking me to loosen one more clamp than I need to. I get the Quick Release. Thanks for the reminder on the front wheel. I get the four bolts on the BB clamp. This is the only place with four bolts. So, we have to slider place left. One permits you to slide what I'll call the handle bar thingy up and back (the one that impacts the measurement that we see). The other one permits you to slide the handle bar thingy while attached to the boom so that the two pieces - connected together by one of the clamps - move as a unit. So, why loosen both clamps?

 

[velocio]

So we can share the same terminology I made this spiffy drawing showing my understanding of what's what. I think (maybe?) this corresponds to official Cruzbike HQ approved terminology ...

From the photo included in the original message in this thread showing the chainstay and an arc towards the fork I thought you were trying to adjust the position of the cranks for your leg length. Yes? On re-reading everything I'm no longer clear on that and suspect you may want to keep the cranks in the same position, but just slide the handlebars more towards the seat. Mebbe?

If you want to adjust the crank position, while keeping the same handlebar position, both the pivot clamp and boom clamp must be loosened (along with everything else). This allows the boom to move in/out of the slider to hold the H'bar position (more or less) and the boom/slider assembly to pivot with respect to horizontal as required by the changing height of the BB.

If you want to adjust the handlebar position, while keeping the same crank position, both the pivot clamp and boom clamp must be loosened (but nothing else). This allows the boom to move in/out of the slider and the slider to slip through the pivot clamp (without pivoting with respect to horizontal or changing location of the BB).

Clear as mud? By the way, I'd be happy to hear that I'm confused on any of this. I'm still figuring this out myself...

-Jack K.

 

[bladderhead]

According to the @velocio diagram, it was the slider that I cut in order to get the bars closer to the BB. Hulk smash, but Bruce Banner uses a hacksaw. If you want to move the BB without moving the bars, I think you have to loosen the boom clamp and keep the pivot clamp tight. It will still pivot. If you want to move the bars and keep the BB where it is, loosen the pivot clamp and keep the boom clamp tight. If you loosen them both at once you will get in a bit of a muddle. I always loosen the bolts on the clamp that holds the BB shell onto the boom. But I think Cruzbike have stopped making a BB-boom interface like mine, anyway.

If you move the BB in a long way, you might find the bars are touching your thighs. Makes it hard to do tight turns. This is the advantage of short cranks. You get an effectively shorter boom and lower knees at the same time.

 

[velocio]

... If you want to move the BB without moving the bars, I think you have to loosen the boom clamp and keep the pivot clamp tight. It will still pivot.

Good to know. I didn't test it, but assumed the pivot action would be impeded if the pivot clamp wasn't loosened.

If you want to move the bars and keep the BB where it is, loosen the pivot clamp and keep the boom clamp tight.

Hmmm... The only Cruzbike I've ever seen in person is my own S40, so I can only speak to that, but ... The boom clamp locks the boom and slider together on my S40, so loosening the pivot clamp alone doesn't allow anything to be moved.

If you loosen them both at once you will get in a bit of a muddle.

It wouldn't be my first muddle, by any means.

I always loosen the bolts on the clamp that holds the BB shell onto the boom. But I think Cruzbike have stopped making a BB-boom interface like mine, anyway.

Which Cruzbike are you referring to? As I said, I've only ever seen the one I own.

If you move the BB in a long way, you might find the bars are touching your thighs. Makes it hard to do tight turns. This is the advantage of short cranks. You get an effectively shorter boom and lower knees at the same time.

I have some 155mm's on order. If the crank swap goes anything like it did on my B-brand Giro then the shorter cranks will be better in pretty much every way. I'm hopeful!

Cheers,

-Jack

 

[paco1961]

Love my 155s. Never going back

 

[bladderhead]

The boom clamp locks the boom and slider together

You are right. My mistake. My username is appropriate. Loosen the pivot clamp. That allows you to move the bars and the BB at once without effecting the distance between them. Tighten the pivot clamp amid loosen the boom clamp and move the BB back to where it was.

My Silvio was made in 2014 and was the absolute leading edge then. Cruzbike are a bit like Apple.

 

[david_kcmo]

So we can share the same terminology I made this spiffy drawing showing my understanding of what's what. I think (maybe?) this corresponds to official Cruzbike HQ approved terminology ...
View attachment 9344
From the photo included in the original message in this thread showing the chainstay and an arc towards the fork I thought you were trying to adjust the position of the cranks for your leg length. Yes? On re-reading everything I'm no longer clear on that and suspect you may want to keep the cranks in the same position, but just slide the handlebars more towards the seat. Mebbe?

If you want to adjust the crank position, while keeping the same handlebar position, both the pivot clamp and boom clamp must be loosened (along with everything else). This allows the boom to move in/out of the slider to hold the H'bar position (more or less) and the boom/slider assembly to pivot with respect to horizontal as required by the changing height of the BB.

If you want to adjust the handlebar position, while keeping the same crank position, both the pivot clamp and boom clamp must be loosened (but nothing else). This allows the boom to move in/out of the slider and the slider to slip through the pivot clamp (without pivoting with respect to horizontal or changing location of the BB).

Clear as mud? By the way, I'd be happy to hear that I'm confused on any of this. I'm still figuring this out myself...

-Jack K.

Thank you for your drawing. So, here goes. You were/are correct. I was trying to adjust the position of the cranks for my leg length. For some reason, and perhaps because geometry was never my thing, I thought that there was more than one way of doing that. However, I guess I'd like to see a drawing of the full path that the BB can go based upon adjustment of the boom. It's not just up and down. I'm thinking that there is some side to side as well. Meaning, the full range is some type of arc. Originally, I was trying to adjust it so my knees don't hit the handle bars while keeping the right leg length. From what I"m seeing, I think you have to deal with the BB position first - this requires you to: (a) loosen the quick release (front wheel, yes, I got that part!) - this is because the bar connecting the BB to the wheel hub will actually rotate in a clockwise and counterclock wise fashion around the wheel hub; (b) loosen the 4 bolts at the BB as this will allow the angle of the boom and whatever the other bar is to change; (c) ....wait wait wait - Now i'm confused. If I were to loosen the pivot clamp - along with the bolts and the QR - shouldn't I be permitted to change the position of the BB? Similarly, if i didn't loosen the pivot clamp but loosed the boom clamp (and the others ones previously) mentioned shouldn't i be able to move the BB? Are these the same things! [Gif of head exploding]. Somehow I am down to "4" on the measurement side of the Boom (from a 6) without bumping my knees. Just don't know how. Is this the 8th wonder of the world! Help

 

[benphyr]

Merry Christmas and welcome to Cruzbike. (That is when you started on the forum I think.)

Anyway, as a general resource Cruzbike has CRUZBIKE OWNER RESOURCES near the bottom of each product page above the Instagram photos where there is a repository of Guides and Videos. Use the Fit and Adjustment video for your model (or any of them - they really are very similar) to visually see how to set up the bike to a good initial setup using the order Robert suggests to make the job as easy as possible. Now that you know how you can make any tweaks that you need to from there.

Like you said, leg extension is going to be set up before handlebar. You are fairly medium in height so you should have no problems getting things to fit. Feel free to take some pictures and ask for advise if you run into a specific question. This forum is a great help.

 

[Merczak73]

This is a really good thread. After reading it, I went ahead and extended my slider by 1-2 mm without moving the handlebar distance.

Holy Cow! Moo Moo Moo! Amazing how 1-2 mm makes a big difference on the feel of the bike. Granted, I am on my Wahoo Kickersnap trainer, but that is as good as I've felt on the S40 in a while. I might try to extend just a bit further tonight - we shall see.

For me, BTW, I loosen everything. The clamp, pivot and MBB as well as quick release. That allows everything to move for me without binding. I guess I am lucky that the whole front end has not fallen apart. I then tighten it all back up. Kinda fun, actually.