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Greenspeed Magnum SeatSide Mount Kit (Back of Seat)

5 reviews
SKU: SMK330.1

We have run out of stock for this item.

One of the great things about triking is how nice it is to have everything right at hand as you roll along. With a SeatSide mount, you can have all sorts of things close at hand. The Magnum SeatSide Mount lets you carry bags, water bottles, cameras, all sorts of things, right by your side. Snacks, phones, lip balm, you name it, now you can keep it all within reach while riding. This mount attaches to the horizontal brace on the back the seat. The mount comes out and forward to your side. The SeatSide arm can be attached on either side, or both if you wish.


1. How does it work?

Specially machined clamps attach to the middle of the back of the seat frame, on the straight part between the bends. A support tube comes out sideways and down from the seat mount clamps. The end of the support tube has a T clamp that holds a horizontal accessory mounting tube. The accessory mounting tube is long enough to hold whatever you'd like.

2. Which side does it go on?

Either, or both, with the double sided option. It's up to you.

3. What can you put on it?

Anything that you can attach to a standard 7/8in (22.2mm, standard handlebar size) tube. So, most anything that's made to be mounted to a bike. Most people attach handlebar bags, water bottles, phones, things like that. The supplied accessory mounting tube is 11 inches (28cm) long, so you have lots of room for both a bag and a bottle, for instance. We have longer tubes if you really want to go crazy.

4. How much weight can it hold?

A lot, but obviously it has it's limits. We're saying 10lbs (4.5Kg) to be on the safe side. We do recommend that if you want to carry living things (like pets) that you do so carefully.


Installation is straightforward.

  1. First, you attach the clamps to the back of the seat.
  2. Next, you assemble the accessory mounting tube to the T-clamp on the support tube.
  3. You then slide the support arm into the seat clamps and adjust the system to the left/right, up/down, and forward/back position you'd like.
  4. You're ready to install your accessories!


  • We include a user installed catchpost in case you want to use a handlebar bag that is designed to index to the handlebar stem on an upright bike. Some handlebar bags have a cable or an arm that is designed to catch on a handlebar stem to keep the bag from rotating down. The catchpost provides a place for that to connect.
  • We make a lot of tubes and clamps that are compatible with this system if you need to do customizations.
  • Clamps are CNC machined aluminum, anodized black, with all stainless fasteners. Tubes are black powder coated aluminum with removable black end caps.
  • Fits all Greenspeed Magnum trikes.
Customer Reviews
4.6 Based on 5 Reviews
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Filter Reviews:
Christopher L.
United States United States
Side mount for Magnum XL

Fit perfectly with no steering interference. Having a side bag really makes my rides more enjoyable. Well worth the money.

Don C.
United States United States
Dual sided Seat-side Mount Kit.

I purchase the dual-sided seat side mount kit and am very happy. Sturdy lightweight aluminum components. The installation was easy. Allows for infinite tweaking so you can find that perfect position to fit your needs. The Terra-Cycle team made sure that the unit fit the XL version of my AWESOME Greenspeed Magnum XL trike. Thanks guys!! Great product.

james s.
United States United States
Greenspeed Magnum SeatSide Mount Kit

The side seat mount is perfect. I should have bought one for the other side.

Robert M.
Addendum to previous review, the new clamps work!

The new clamps you sent me were a huge improvement. Thank you for the excellent customer service!

Robert M.
United States United States
Poor strength

Low weight limit. Clamps attached to seat back would slide around the seat attachment(less than 5 pound load). Attempted to tighten but bent clamps. Bent them back as best as I could and added a third clamp. So far seems to be working.


Hey Robert, We've recently upgraded the clamps that are used to hold the SeatSide Mount to the back of the bike. With your blessing, I'd love to send you a pair and see what you think! -Caz