I broke my Perez Clamps and Cruzbike is out of stock...alternatives?

[Jesse Groves]

I noticed this morning that my neckrest was moving forward anytime I hit the brakes. I pulled over and tightened the screws to the Perez Clamps a bit, but the problem persisted. When I got home, I took the seat off and the metal casings that the bolts screw into had pulled out of the clamping blocks so that they weren't holding the bars in place; this also made it a PITA to remove them...anyway, after working on it for an hour, the clamps are out, but ruined.

I went to the CB site to order some more and they are out of stock. So, my question is what is the alternative? I wrapped some electrical tape around the two bars where they insert into the frame and that helps hold them in place, but not very firmly.

What were people using before the Perez Clamps?

Thanks,

 

[LarryOz]

Jesse, email Robert at Cruzbike (robert@cruzbike.com) and he can probably send you some of the original clamps if he has any - and I am pretty sure he will. They are kind of PITR (Pain in the Rear) to put in themselves, but once in they will not move or come loose.

Are both of the Perez clamps damaged? One of mine stripped out like yours, and I am just using a single one now and it is fine.

 

[Jesse Groves]

Both of them were damaged. I will email Robert in the meantime.

Thanks

 

[Lief]

Jesse. I can send you my current ones and take the back order from Cruzbike if that helps. I’m not currently riding on mine.

 

[Jesse Groves]

Jesse. I can send you my current ones and take the back order from Cruzbike if that helps. I’m not currently riding on mine.

Thanks Lief, but Robert is sending me some of the old ones to use until the new ones are back in stock.

 

[super slim]

What I did was to remove the very heavy solid SS bar, on the Cruzbike version, that stops the two clamps rotating, while the clamps are loose, and just used a 90 degree screwdriver while the clamps are loose.
Once near fully tightened, the length of the clamps stops them turning.
I replaced the short allen screws with Silicone greased 30 mm long allen screws, so it goes fully through the WHOLE clamp as originally designed by Jason.
I used a Metric tap to hand tap out the thread, for the whole depth of the clamp, minus the dia drilled out for the SS solid bar.
I added a grease covered on both sides, SS washer to reduce the friction with the Allen screw head and the Aluminium frame, and hence increase the clamping force, for the same tightening torque.
I made certain that the rubber sleeves were in the area of the two clamps, so that there was increased friction between the headrest tubes and the clamps, AND there was a spring effect on the two Allen screws to stop them rattling loose.

If the threads and the metal inserts, of the damaged clamps are only damaged, then an option could be to tap the threads for the FULL depth of the clamp to a M8 1.25 mm pitch, OR one of those funny coarse UNC threads, the coarser the thread, the better for thread depth, to reduce thread pull out.

Lubrication of the bolt and washer is also important, to reduce the torque required to clamp the headrest tubes securely!

 

[ratz]

Thanks Lief, but Robert is sending me some of the old ones to use until the new ones are back in stock.

When you get the temp old ones be advised: You'll find once you get them in the frame and the screw installed, you have to Unscrew the bolts to almost the max and then push the screws all the way into the frame to get the the clamp to shape for clean inserting of the pipes. It's a PITA and there some photos in my build diary in my signature that will save you a bunch of grief if you've looked at it ahead of time.

It's fiddly and when you are already frustrated with a part failure it runs the risk of being maddeningly futzy.

 

[RojoRacing]

So wait are these clamps that are failing the ones I made or the ones that cruzbike had made? I can kind of picture the helicoils pulling out on my very first few since they only grab 1/3 depth but the version 2 had no coils and just threaded the full depth to fully use the strength of the long bolt. You're not going to strip version two unless you try using a short bolt or had a gorilla help you torque them down.

 

[tiltmaniac]

I modded my CB supplied Perez clamps by drilling a hole for the solid rod off-center. I then tapped the bottom part of the screw hole to provide additional threads for the screw to bite into.
This worked much better for my purposes, which was to mount the seat as well as fix the headrest.

 

[super slim]

So wait are these clamps that are failing the ones I made or the ones that cruzbike had made? I can kind of picture the helicoils pulling out on my very first few since they only grab 1/3 depth but the version 2 had no coils and just threaded the full depth to fully use the strength of the long bolt. You're not going to strip version two unless you try using a short bolt or had a gorilla help you torque them down.

Jason I assume the broken ones, are the Cruzbike version with a central rod so the bolt only goes 1/3 of the clamp depth with a SS helicoil.

 

[RojoRacing]

Oh I didn't know the CB ones used a helicoil like my first ones, now everything makes more sense. Still @LarryOz you said you stripped one was that the original one you got from me or a CB one?

Also if anyone is using only one clamp instead of the intended two you're more likely to pull out the threads with normal use because leverage on the single point of contact.

 

[super slim]

Here is a photo of the cruzbike version of Jason's Headrest clamps!

 

[RojoRacing]

Mass production vs limited production with pride, sacrifices will be made.

Speaking of pride I would really like to hear about any of my personally made clamps failing. I take pride in everything I design and make so I want to know if my stuff is failing.

 

[RojoRacing]

When you get the temp old ones be advised: You'll find once you get them in the frame and the screw installed, you have to Unscrew the bolts to almost the max and then push the screws all the way into the frame to get the the clamp to shape for clean inserting of the pipes. It's a PITA and there some photos in my build diary in my signature that will save you a bunch of grief if you've looked at it ahead of time.

It's fiddly and when you are already frustrated with a part failure it runs the risk of being maddeningly futzy.

:lol thus the reason the Perez clamp was born. Innovation out of frustration could be my business moto.

 

[ratz]

Mass production vs limited production with pride, sacrifices will be made.

Speaking of pride I would really like to hear about any of my personally made clamps failing. I take pride in everything I design and make so I want to know if my stuff is failing.

Rock solid prefer the 4 I have from you to the production ones

 

[Jesse Groves]

Jason, as noted by others, the clamps I have did not have the bolt going all the way through...admittedly, that did not stop me from thinking to myself while wrestling to remove them that this Perez guys has got some 'splainin to do!

Bob, I will make sure to check out the thread you mentioned if it gets to that point. I am going to try to use the ones I have and do like others have mentioned and drill them all the way through and install them without the connector rod.

 

[RojoRacing]

Jason, as noted by others, the clamps I have did not have the bolt going all the way through...admittedly, that did not stop me from thinking to myself while wrestling to remove them that this Perez guys has got some 'splainin to do!

Bob, I will make sure to check out the thread you mentioned if it gets to that point. I am going to try to use the ones I have and do like others have mentioned and drill them all the way through and install them without the connector rod.

Bwahaha the CB clamps are giving Rojo Engineering a bad rap how ever will my stock prices recover.

 

[Jesse Groves]

So I did like others suggested and modified the non-Perez "Perez" Clamps. I removed the bar attaching the two pieces, drilled all the way through, inserted some little metal inserts through the bottom side and then bolted through from the top. The inserts have little spikes that dig into the plastic perfectly and hold them in place so they dont spin when you try to tighten them.

Thanks everyone for the advice.

 

[RojoRacing]

Hey Jesse just checking in to see how those clamps are holding up

 

[Jesse Groves]

Hey Jesse just checking in to see how those clamps are holding up

Still working now that I modified them so the bolt goes all the way through. In fact, only one of them is being used right now because I have the neck rest so far out of the frame. I've been riding like that for a while now and I've had no problems with the neck rest moving.