Crash

[Brad R]

The only way I could make any kind of sense of the mess was to position anther bike next to it and see how it all went together. But I wonder why the Cruzbike design of the wheel drop-outs are such that this is necessary. Every other bike made is not like this.

A T50 has what you would recognize as a “normal “ dropout. As the boom length is adjusted, the chain stays rotate around a point that is not coincident with the axle. This causes two undesirable things to happen. (1)The length of chain needed changes because the distance from the axle to the bottom bracket changes. (2) The angle of the derailleurs with respect to the chainline changes.

With a high capacity rear derailleur, you don’t normally have to change the actual chain length for a pretty wide range of adjustment, but it is not ideal.

The V, S, and now Q allow the chainstay to rotate around the axle as the boom length is adjusted. This keeps all of the chainline and derailleur geometry the same. This has obvious advantages for riding and setting up the bike. It has the disadvantage if the chainstay gets separated from the fork when you remove the wheel.

 

[tiltmaniac]

A T50 has what you would recognize as a “normal “ dropout. As the boom length is adjusted, the chain stays rotate around a point that is not coincident with the axle. This causes two undesirable things to happen. (1)The length of chain needed changes because the distance from the axle to the bottom bracket changes. (2) The angle of the derailleurs with respect to the chainline changes.

With a high capacity rear derailleur, you don’t normally have to change the actual chain length for a pretty wide range of adjustment, but it is not ideal.

The V, S, and now Q allow the chainstay to rotate around the axle as the boom length is adjusted. This keeps all of the chainline and derailleur geometry the same. This has obvious advantages for riding and setting up the bike. It has the disadvantage if the chainstay gets separated from the fork when you remove the wheel.

Well, with the current design, anyway.

A set screw or two for the hangar, plus a flanged mate design for the fork-chainstay interface would prevent this need.

 

[DavidCH]

Two zip ties placed on the opposite side will keep the assembly together. First ensure chain is off chainwheel. Put bike on its side with deurallier on top. Removing the axle in a downwards fashion will keep the assembly together @trplay is the superstar of this technique

 

[Kenneth Jessett]

Two zip ties placed on the opposite side will keep the assembly together. First ensure chain is off chainwheel. Put bike on its side with deurallier on top. Removing the axle in a downwards fashion will keep the assembly together @trplay is the superstar of this technique

I'm torn whether to try this now in the comfort of my own home, or wait until I am out in the cold (metaphorically) and suffer the trials and tribulations of a road side fix - and maybe a long walk home. I think on reflection I'll go with a training session out on the back lawn and see how it all comes together. Thanks for the ideas.

Ken.

 

[tiltmaniac]

I'm torn whether to try this now in the comfort of my own home, or wait until I am out in the cold (metaphorically) and suffer the trials and tribulations of a road side fix - and maybe a long walk home. I think on reflection I'll go with a training session out on the back lawn and see how it all comes together. Thanks for the ideas.

Ken.

Home.

 

[Bill K]

I think on reflection I'll go with a training session out on the back lawn and see how it all comes together.

I heard of a randonneur who tested his bike repair capabilities by changing a flat tire on his front lawn, at night in the dark, and with the sprinklers turned on. No need to wait until you are away from home and out in the cold

 

[Gary123]

Zip ties help but derailleur side can still come apart if not careful. There should be a way to keep this from happening.

 

[bladderhead]

I taught myself to do it sideways at home and recently I successfully did it in the street. Oo-er! Your front tyre will get a puncture eventually. Teach yourself to do it at home, or get solid tyres.

What it needs is magnets in the dropout and chainstay.

 

[Kenneth Jessett]

Zip ties help but derailleur side can still come apart if not careful. There should be a way to keep this from happening.

Yes there should. I think it's a design flaw that needs to be rectifide for future models.

I'm of the feeling now that I wouldn't want to ride the V out on the open road when realistically getting a puncture is the norm and having to fumble around for zip ties and the like and trying to figure out how it all goes together again will be too much. On my standard bikes I use Continental Gatorskins but even then I do get the occasional puncture - particularly in the rain - so it will happen sooner or later on any bike. Maybe solid tyres is the answer.

 

[Gary123]

It's really not that difficult. Zip ties can stay on left side permanently but right side can still come apart and drop derailleur. I've never changed flat on the road but had 2 short walks home after flatting. I'm sure it's much easier repair in the garage. I'm working on a solution. Any advice?

 

[cpml123]

I have zip ties on both sides. Seems to be fine and not interfering with anything

 

[Kenneth Jessett]

Is the S40 built the same way? I'd like to hear from those who tour on Cruzbikes how they have dealt with the issue.

Maria has raced across the country on RAAM, so I assume with the follow vehicles if she had any flats, the crew would have raced in and taken care of it. I need a follow vehicle when I ride in that case, I should look for a volunteer.

 

[ElyDave]

Zip ties where? I can't quite picture this - to many other things taking limited brain space at the moment.

Permanent, or each time you need to change the wheel out? I'm thinking Turbo trainer here

 

[1happyreader]

Zip ties where? I can't quite picture this - to many other things taking limited brain space at the moment.

Permanent, or each time you need to change the wheel out? I'm thinking Turbo trainer here

search forums : check out beginning of this thread " zip tie front triangle" http://cruzbike.com/forum/posts/141541/

 

[Kenneth Jessett]

search forums : check out beginning of this thread " zip tie front triangle" http://cruzbike.com/forum/posts/141541/

In that note, Gary said:
I think the better question is why can't the fork be made to stay intact without zip ties.

And the partial answer came: "it’s a concession to weight". Which is rather silly since there is more material than if they were open ended.

We need a better solution than having to hold the whole thing together with zip ties. I shall have to take a closer look to all this and see if there isn't a reasonable way forward.