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MattTuck
03-24-2017, 03:03 PM
I know we saw that crazy rig a few weeks back for setting everything up to the nanometer.

This device from Abbey Bike Tools actually looks like it is 'back to basics' and much better than some of the other methods I've tried, including balancing a book on the saddle to get a good tilt measure, and a nice consistent way to get a fore/aft measure.

https://cdn-cyclingtips.pressidium.com/wp-content/uploads/2017/03/NAHBS-Abbey-Bike-Tools-7.jpg

shovelhd
03-24-2017, 07:41 PM
Everything that Abbey makes is just outstanding.

abr5
03-24-2017, 08:03 PM
Very interesting, more info here. I'm not sure if I'd pay $150 though..

https://www.bikerumor.com/2017/03/14/nahbs-2017-abbey-bike-tools-takes-guess-work-saddle-measurement-teases-rock-shox-tools/

Ray
03-25-2017, 07:50 AM
I remember something similar several years back called the FitStik or something along those lines. It worked but was about $100. I ultimately found that nothing worked as well as a vertical post in my basement, with square edges. Once I had a bike set up just right, I could line up the BB bolt with one of the edges (usually by sticking a hex wrench in it and pushing it up against the post), do a series of measurements from there, and then easily be able to replicate that position using the same basic method. Was dead-cheap and insanely effective... I was a real princess and the pea with saddle position too - I could handle some discrepancy in bar position, but the saddle relative to the cranks had to be dead-perfect...

-Ray

Cicli
03-25-2017, 08:04 AM
Very interesting, more info here. I'm not sure if I'd pay $150 though..

https://www.bikerumor.com/2017/03/14/nahbs-2017-abbey-bike-tools-takes-guess-work-saddle-measurement-teases-rock-shox-tools/

Like another poster stated. Abbey tools are outstanding. Do I always spend the money for them? No. They are the best though.

FriarQuade
04-05-2017, 11:57 AM
These should be available in late May for anybody that's interested. We moved the saddle height bullets to the back corner running down the length of the plate instead of across it. This allows you to use the toe strap to attach a level should you want to use the plate to get a bar drop measurement.

bluesea
04-05-2017, 02:05 PM
I like the strange jigs they built for Merckx featured in "A Sunday in Hell".

benb
04-05-2017, 02:17 PM
FriarQuade, how do you use this to measure setback? Drop a plumb bob from it or sight through the hole or something?

FriarQuade
04-05-2017, 02:56 PM
FriarQuade, how do you use this to measure setback? Drop a plumb bob from it or sight through the hole or something?

Drop a plumb off the edge of the plate. You do the setback at the top and then shoot for axle center. The plate adds enough width so the plumb will clear bottle cages and whatever else you've got bolted to your bike. It's not the most intuitive thing to look at but once you start playing with everything you can figure it all out in 5 minutes or less. We will get some more descriptive photos on the site.

benb
04-05-2017, 03:26 PM
Drop a plumb off the edge of the plate. You do the setback at the top and then shoot for axle center. The plate adds enough width so the plumb will clear bottle cages and whatever else you've got bolted to your bike. It's not the most intuitive thing to look at but once you start playing with everything you can figure it all out in 5 minutes or less. We will get some more descriptive photos on the site.

And the straps secure it to the saddle while you do this?

I like the idea of a tool like this but I've pretty much given up on plumb bobs and instead use a measurement from the wall for setback. I'm sure this tool helps a lot but I guess I wonder if it improves the plumb bob technique enough to be better than measuring from a wall. The plumb bob technique is still more error prone with the tool than a wall measurement is if the floor isn't perfectly level.

MattTuck
04-05-2017, 03:33 PM
And the straps secure it to the saddle while you do this?

I like the idea of a tool like this but I've pretty much given up on plumb bobs and instead use a measurement from the wall for setback. I'm sure this tool helps a lot but I guess I wonder if it improves the plumb bob technique enough to be better than measuring from a wall. The plumb bob technique is still more error prone with the tool than a wall measurement is if the floor isn't perfectly level.

I tried the measure to the wall trick. It has its own set of draw backs. It is very hard to be sure you're taking a level measurement vertically, and measuring from the bottom bracket is generally complicated because of the chain stays, seat stays and or hub and spokes. Same issue with vertical level as with the saddle.

FriarQuade
04-05-2017, 07:02 PM
And the straps secure it to the saddle while you do this?

I like the idea of a tool like this but I've pretty much given up on plumb bobs and instead use a measurement from the wall for setback. I'm sure this tool helps a lot but I guess I wonder if it improves the plumb bob technique enough to be better than measuring from a wall. The plumb bob technique is still more error prone with the tool than a wall measurement is if the floor isn't perfectly level.

The key is to make the bike static. If you're trying to hold the bike with one hand and take measurements with the other you're not going to get good data. This is why the schmo tour teams use the bike settings jig while the bike is in a euro style repair stand. That system has it's own set of problems though. If you put the bike in a trainer and level the bike or put it in a stand with both wheels on the ground you will have a much better time getting good numbers and repeating them. Using a system like ours makes those numbers more accurate.

At the end of the day there's still a person sitting on the bike and how they interact with these variables is nearly impossible to quantify, even if you do go down the rabbit hole of saddle flex, shoe sole thickness, stem length variance, bar width tolerance the list goes on.

benb
04-06-2017, 08:48 AM
The thing is the % error is much smaller if you're using the tape measure from the wall.

When you measure out from the wall you're measuring the long side of a triangle (assuming something is not perfectly level), when you use a plumb bob you're measuring the small side of a triangle to get the setback.

You can do the trig, a degree or two off on the bike being level with the plumb bob generates a much bigger error than if you can't get the measuring tape perfect measuring out from the wall.

I guess it depends on what you have available, I have a good place near my workbench to do the wall trick. A lot of cranks and/or BBs have markings that help you locate the center of the BB as well.

I don't really worry about saddle flex/shoes/whatever cause I'm only measuring for myself.

Regardless I still like the tool, putting it on top of the saddle would make the wall measurement setup work better too as it provides a nice platform to put the measuring tape on and gives you a good reference point to the front of the saddle.

I guess my only other thing that'd be cool with this would be if it had notches at each centimeter mark on the side for hanging the plumb bob instead of just at 5cm, or perhaps even every 5mm.

chiasticon
04-06-2017, 10:35 AM
as someone with multiple bikes who struggles mightily to get them to match up, and who also loves everything Abbey does... this looks awesome.

I love the inserts for various cranksets. would love to see more detail on how they work, specifically with GXP cranksets.

I am a little surprised that even a simple bubble level isn't built into it though.

benb
04-06-2017, 11:03 AM
Guess I may be confused about how this is used, it can slot into the cranks too? That seems like a great design for measuring with the plumb bob. But I didn't think that was what it's for since it's shown on a saddle..

chiasticon
04-06-2017, 11:50 AM
Guess I may be confused about how this is used, it can slot into the cranks too? That seems like a great design for measuring with the plumb bob. But I didn't think that was what it's for since it's shown on a saddle..follow the bikerumor link above and read about it/see pics. the three little bits on the end (under the rubber toe strap) come off of the plate. they attach to various crank bolts and have a slot, with a magnet inside. you then place the end of a tape measure into this slot, magnet holds it in place, and you can measure saddle height from BB center accurately.

simpler and more accurate than measuring saddle height from floor and subtracting BB height from floor.

I'd also like to note that this has a bit of an edge over the purely custom xy tool, which MattTuck alluded to in the original post. with the ability to anchor the plate to the saddle and the insert bolt to the crank, plus have the tape measure "lock" into a centered slot in that, it's a lot less fiddly; and hence, should be more accurate and repeatable. with the purely custom xy tool, you have to use one hand to hold the thing in the middle of your crankset bolt while you do everything else with the other hand.