If you need to add weight to make a class (assuming you intend to race it), then that’d be the easiest approach. Alternatively, if there is clearance between the seat & uprights, you can use washers with long bolts to adjust the lateral positioning to achieve 50/50 balance; if not, then you’ll have to bend them.
I could have been more specific in my previous post. I do race and I’ll never have to add weight. I’m 6’3" and 250 lbs. suited up, hence the XL size seat. I have to bend the seat mounts outward substantially to fit seat. I think most people just adjust positioning of the left side upright mount, but with the extra large seat I’ll end up with more than 15 pounds heavier on the left rear so I bend outward the right side seat mount upright as well to get an even weight distribution left to right. I’m looking for insight as to what is more important. Achieving an equal weight distribution by bending left and right seat mounts or only bending the left mount to fit seat and not bending the right side and living with the unequal weight distribution left to right.
I’m pretty much same size, slightly lighter but close…anyways standard answer is bend left strut only, use seat offset to help. What I personally do, I cheat a little.
Say you have a new chassis so seat stays have to be widened 4 inches. In that case, I get 3 from the left, 1 from the right. If suggested offset is 5mm, I use 10mm and that tends to get me closer.
Chassis are not meant to have the right stay bent, but they are also not designed around a giant. So be careful and don’t overdo it. Also engine clearance could be an issue. My IPK was a breeze, I’m a little tight with clearance on the right side, but it works great for me
Which strut you bend is only relevant to the spacing you have to work with (eg. Like engine & radiator clearance). Even L/R weight distribution should be the goal, & the seat will need to be in a specific location, relative to your weight, to achieve that. You’re introducing setup complications with lateral weight bias distribution.
I’m going through all the seat positioning/installation gymnastics today, and I’m running into a lot of the issues mentioned in this thread. Using the “axle to drivers back” measurement does indeed seem like the magic bullet to cut through all the bs. IMHO, OTK should switch or at a minimum mention the seat size used in their measurements (and how to compensate if yours is different). Thanks to everyone who contributed here for saving me time and hassle.
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Yea, I’m playing this game right now as well. Jecko calls for 11.5-12cm for Axle to drivers back for a shifter(Interesting that Tillett want’s at 13, I guess that’s because of seat back angle differences in between the two seats?)
In any case, I’m just going to go ahead and and send it at 12cm, 1060 from Left Kingpin to top of the seat back and parallel with rails on my IPK Jecko and hope for the best (IPK based chassis)
Tillett calls for a longer measurement because they suggest measuring to the “flat” part of the back of the seat due to variability in the ridge down the middle.
The dimensions you mention are a good starting point. The kingpin to seatback measurement can be a little tricky due to differences in seat back height. Some of the Jecko seats are quite short, so that dimension may measure ~1cm shorter than it would for a standard seat.
This may help a bit , it help me when i was installing jecko seats
I went to buy my first seat recently and upgrade from the one that came with the cart. I opted to have Tommy at Texas Carts do the seat swap for me so I could try to watch and learn. I am SO glad I went that route!