Seat Mod

[Rick Youngblood]

Not now. But I know soreness from contact of tights with seat edge and this is different. I have mounted seat as back as possible. Screws are ~6 cm from seat edge.

Okay. I'm no professional, but my wife is a therapeutic massage therapist trained in deep tissue. It's extremely difficult to diagnose the butt, knee, neck pains, etc, but It sounds like you may have tight glute muscles, maybe or maybe not with some scare tissue residing in the muscle tissue strands that possibly needs breaking down...deep tissue massage can do this...

I had this in my left thigh early last year which was causing pain in the upper side of my knee. My thigh just wasn't elastic enough. I had not been doing enough stretching after rides helping with the healing process. I found a sports massage therapist that has been trained in sports massage and deep tissue...she was able to break it down in about 3 sessions, talk about pain. This helped remove the side knee pain for good.

It may be worth googling how to effectively stretch tight glutes. But don't forget stretching the hamstrings too. Can't say whether or not this will help, but it maybe worth a try.

 

[snilard]

@Rick Youngblood Thank's for support

 

[ccf]

I purchased a Thor seat for my S30 (original, fully-suspended). I'm thinking of mounting it with screws at the wings designed for mounting the original seat, then using Velcro at the point that the Thor makes contact with the frame (up closer to the top of the frame) and also using a tie wrap at the Velcro point. I wouldn't use any rubber mounting. The suspension presumably will absorb a bunch of the road vibration. This is basically how the original seat was mounted.

Any thoughts on that approach?

-Cliff

 

[Doug Kline]

I attached a large Thor G-sport seat to my V20 without mounting blocks. I drilled new holes in the mounting wings on the V20 frame as the holes needed to be closer together to avoid putting any holes in the ribs of the Thor seat. I'm not using the standard headrest mount so I drilled a hole in the middle of the upper back of the seat to use one of the existing holes in the V20 where the scissor jack would go. Then I attached an Adem headrest. It is all solid and working fine.

When I did a similar mount on my wife's V20 using a Volae medium seat I had to add some rubber washers as spacers.

 

[Rick Youngblood]

Blocks or washers are necessary to compensate for the differences with opposing contours between seat and frame, and/or seat support ribs in the front attachment. However, if you're lucky enough to find an aftermarket cf seat that follows the contours of the Cruzbike frame, well then the mounting blocks may not be necessary. I've found that neither Hostel Shoppe or Thor in mediums follow the Cruzbike frame contours, thus requiring some sort of spacer mounting block, but have read some of the larger sized seats follow the frame more closely. But, I have found on the Vendetta the rubber mounting blocks help scrub off a lot of road chime. I personally chose the jewelers ruber because it's easy to work with and it's inexpensive.

 

[ccf]

I drilled new holes in the mounting wings on the V20 frame as the holes needed to be closer together to avoid putting any holes in the ribs of the Thor seat.

Would drilling a 7/32 hole thru the front of each rib at the wings weaken the seat?

-Cliff

 

[Rick Youngblood]

Would drilling a 7/32 hole thru the front of each rib at the wings weaken the seat?

-Cliff

Yes! You don't want to drill through the support ribs. Some cf seat ribs are spaced far enough to use the existing wing holes, in that case you can use the existing frame wing holes, otherwise it will be necessary to drill two new holes to each side of the frame. But you will still need a support bridge that runs across and perpendicular to the frame, as the frame must support the seat and it's passenger and not the wings. The frame wings are not strong enough. The wings are only to secure the seat not support it. The ribs insides are either hollow or have foam, so drilling through this area will defunct the integrity of the rib.

 

[tiltmaniac]

Yes! You don't want to drill through the support ribs. Some cf seat ribs are spaced far enough to use the existing wing holes, in that case you can use the existing frame wing holes, otherwise it will be necessary to drill two new holes to each side of the frame. But you will still need a support bridge that runs across and perpendicular to the frame, as the frame must support the seat and it's passenger and not the wings. The frame wings are not strong enough. The wings are only to secure the seat not support it. The ribs insides are either hollow or have foam, so drilling through this area will defunct the integrity of the rib.

I've drilled through the ribs. Imho, while Rick is right that this likely weakens the seat, it may not do so fatally-- my volae XL worked well with holes in the ribs. My dad's volae L worked well with holes in the ribs too.

There is a huge caveat here, however-- I would not, and did not, put all the weight on the wings.

Some kind of shim between the seat and the main body of the frame is a very good idea.
I believe my mounting worked because the ribs where I drilled the holes were no longer load bearing as I did use shims, like Rick.

 

[Rick Youngblood]

I've drilled through the ribs. Imho, while Rick is right that this likely weakens the seat, it may not do so fatally-- my volae XL worked well with holes in the ribs. My dad's volae L worked well with holes in the ribs too.

There is a huge caveat here, however-- I would not, and did not, put all the weight on the wings.

Some kind of shim between the seat and the main body of the frame is a very good idea.
I believe my mounting worked because the ribs where I drilled the holes were no longer load bearing as I did use shims, like Rick.

This does make sense and is understandable. As I remember, the Volae seat uses a lot more carbon fiber than typical CF seats like Thor, it's quite a bit more substantial and thicker. After watching your tilting trike build, I have full confidence and no doubt in your mechanical skills.

Pictures and explanations here on this thread of yours and others seat mod builds are more than welcomed. I'm sure through this process we can together improve and simply seat mods for others.

 

[Doug Kline]

I agree you don't want to put weight on the wings. In my experience, the large Thor G-sport seat followed the contour of the V20 hydroform tube very well without the need for any shims. I think the medium Volae seat also follows the hydroform tube reasonably well but the ribs were too close together to clear the tips of the wings. So I used rubber washer spacers to raise the seat slightly to keep the rib from touching the wing. That *may* be putting some weight on the wings, and it is possible I should have used a small shim. If I could have trimmed the wings it would have fit perfectly, but I wasn't willing to do that. In all honesty my wife hasn't ridden it so no real world test on it yet. Before bolting it down, we tried it on the trainer just attached with velcro and it was stable and is feels very solid when I sit on it.

Hopefully your experience with the S30 is similar.

 

[Rick Youngblood]

I agree you don't want to put weight on the wings. In my experience, the large Thor G-sport seat followed the contour of the V20 hydroform tube very well without the need for any shims. I think the medium Volae seat also follows the hydroform tube reasonably well but the ribs were too close together to clear the tips of the wings. So I used rubber washer spacers to raise the seat slightly to keep the rib from touching the wing. That *may* be putting some weight on the wings, and it is possible I should have used a small shim. If I could have trimmed the wings it would have fit perfectly, but I wasn't willing to do that. In all honesty my wife hasn't ridden it so no real world test on it yet. Before bolting it down, we tried it on the trainer just attached with velcro and it was stable and is feels very solid when I sit on it.

Hopefully your experience with the S30 is similar.

Hi Doug! It's not so much the weight of the seat and rider, as it is the extra downward force that will be impacted between wing and rib. For example when you hit a bump or pothole there is a lot of downward force in play. I would suggest to shim the front of the seat up a little higher along with a center support shim, so as to have enough clearance between the rib and wing. Or place a shimming block between the frame seat, so that all your seat is supported by the frame and not the wings, and use the wings only to hold the seat in place as John T. intended.

Also just as note for all that is working this mod, pay attention to the front of the seats lip when placing the seat on the Cruzbike frame, so that it's not so high that it touches the back side of your thighs or but. You're able to rotate the seat front to back. As it rotated to the front the, the front lip is raised and the back is lowered, as it's rotated to the back the front is lowered and the rear is raised. There should be a happy median that rotates the seat so there will be no thigh interference. None of my seats followed the contour of the Silvio or Vendetta frame enough to not use some sort of spacer, especially in the rear mount. I found that if the rear of the seat touched the frame, the front of the seat would be too high and therefore interfere with my extended stroke of pedaling.

 

[ccf]

My size large Thor seat makes contact with the S30 frame at three points (see diagram). This configuration produces a good orientation for the seat (see photos comparing original seat and Thor seat). The point of contact at the wings looks like the attached photo of the underside of the Thor seat. I could place a small plastic block across the frame at that point and drill new holes in the wings to avoid the ribs of the seat. If the plastic spacer were about 10mm thick, it would just prevent the wings from touching the front of the ribs. A rectangular spacer would sit on the welds connecting the wings to the frame because they stick up a little above the frame. Would that be acceptable, or should I file grooves in the spacer so that it sits squarely on the flat part of the frame ?

-Cliff

 

[Rick Youngblood]

My size large Thor seat makes contact with the S30 frame at three points (see diagram). This configuration produces a good orientation for the seat (see photos comparing original seat and Thor seat). The point of contact at the wings looks like the attached photo of the underside of the Thor seat. I could place a small plastic block across the frame at that point and drill new holes in the wings to avoid the ribs of the seat. If the plastic spacer were about 10mm thick, it would just prevent the wings from touching the front of the ribs. A rectangular spacer would sit on the welds connecting the wings to the frame because they stick up a little above the frame. Would that be acceptable, or should I file grooves in the spacer so that it sits squarely on the flat part of the frameView attachment 4080 View attachment 4081 View attachment 4082 View attachment 4083 ?

-Cliff

Hey Cliff. What I would do, is use the dense rubber found on eBay, there should be a link in this thread. It's just so easy to work with and it's also very forgiving. By using the rubber, there would not be a need for a perfect conformation between frame.seat.block. The rubber block would pretty much conform itself simply by bolting down the seat and rider weight. For the rear attachment, I would use some sort of rubber or nylon washer between the frame and seat.

TIP - drilling block, seat, and frame wings: Measure and mark the center point for drill holes on the winds to each side of the frame. Be sure and allow enough clearance for stainless steel washers and nuts between new hole and frame on the underside. Now position the block and seat on the frame in the exact location you want it to be. If using a block or spacer in the rear just tape it in place. Use a strap to firmly secure the seat to the frame, front and back. I use Velcro straps. Check to make sure everything is lined up. Sit on, check the front lip for thigh clearance. Make adjustment if needed. Once you are happy with its position...drill from the bottom of your pre-drilled wing hole, through the block and seat...you will then have perfectly aligned front holes running through the seat, block and frame.

As an after thought. If the weld is 1-2mm high, I wouldn't be too concerned about it. I don't remember having this issue with my Silvio 2.1 or Vendetta 2.0.

Also, you don't want the front of the seat lip touching the frame, otherwise it will rub into the paint and you will end up with an ugly black mark.

 

[super slim]

Cliff, from the photos of standard and the Thor seat, the position of the seat front lip looks very similar!

What is the dimension from the front edge of the wing to the front edge of the seat, for the two seats, and what are the dimensions for the other Thor converts?

 

[ccf]

What is the dimension from the front edge of the wing to the front edge of the seat, for the two seats, and what are the dimensions for the other Thor converts?

The front edge of the Thor is a little over 2 inches forward of the holes in the wings (near edge of black tape). The front edge of the Cruzbike seat is a little over 1 inch forward of the holes in the wings (near edge of grey tape).

-Cliff

 

[super slim]

CCF this is what Rick did on his Big Yellow, by drilling two extra hole in the wings, and adding a shaped rubber block between the seat and the frame.
A picture is worth a thousand words!

 

[ccf]

CCF this is what Rick did on his Big Yellow, by drilling two extra hole in the wings, and adding a shaped rubber block between the seat and the frame.
A picture is worth a thousand words!

I'm going to do the same thing. I ordered the rubber already. I could cut off the ends of the wings to help avoid interference with the ribs of the seat. That would allow me to use a block with a lower height. But I think I'll keep the wings as-is and go with a taller block.

-Cliff

 

[tiltmaniac]

You should also look at the thermoplastic way of doing it, as described here: http://cruzbike.com/forum/threads/s30-buildup-with-volae-comfort-carbon-l-seat.11469/#post-130440

The seat is very secure with the getup in that thread, though you don't get the advantage of the extra suspension, you also don't need to drill other holes in the frame.
I just got a Thor Sport G L seat yesterday, so I'll be playing with mounting it on my new-to-me S30 (#2) on the weekend.

 

[ccf]

In the end I did things a little differently than @Rick Youngblood. I used 1/8-inch thick rubber gasket material from Ace Hardware to form a spacer by cutting the rubber in the shape of the wings, shortening the width to 3 inches to provide clearance for the ribs of the seat. I used two layers of rubber to form a 1/4-inch thick spacer. I attached the layers to each other and to the wings with double-sided carpet tape. I drilled new holes in the wings 2.5 inches on center and attached the front of the seat to the frame with M5 0.8 screws. Even with just a 1/4-inch spacer, the ribs clear the wings. I used Velcro to attach the seat to the frame at the other two points where it makes contact. See photos.



I took the bike out for an easy ride today. The Thor seat feels like a bucket seat in a sports car. At first the front end of the bike felt lighter and a bit twitchy. I think that is because the thoracic support of the Thor allowed my upper body to relax more and caused me to use a lighter touch on the bars with no pulling. That's exactly what I was aiming for. By the end of the ride it didn't feel twitchy any more. When riding hands-free I was able to apply pressure to the bike at my shoulder blades independent of the control from pedaling, which gave me more control of the bike. As a result, I set a personal distance record for hands-free riding. I was able to create good power uphill without pulling. I went up the final, short 15% grade to the house without pulling on the bars at all.

 

[Gary123]

Nice "setup"