Changing rear shocks on Yamaha YBR 125 Custom

[mikeyb7]

Hi,

I'm looking at changing the rear shocks on my Yamahe YBR Custom and was after some advice please.

I want to raise the seat height as it's particularly low. The current shocks seem to be 340mm in length, can I put any length shocks on, i.e 360mm, 380mm?

I've read that changing the shocks can change the trail on the front wheel, does anyone know what affect putting 380mm shocks on would cause?

Any help much appreciated!

Thanks,
Mike

[mikeyb7]

Hi,

Sorry to be a pain, just wondered if anyone had any advice concerning these rear shocks and increasing seat height?

Thanks again,
Mike

[P.]

It is the custom which is cruiser-esque, which is why it's low.

You 'could' just stick bigger shocks in there. Problem being it'll probably handle like garbage. You can do things to resolve that, adjusting the front end to match but you are talking 20mm+ on the rear (which won't be a massive height increase) which means you'll need to rejig that front a fair bit... From what I remember, the custom just doesn't have much scope to drop forks at the front too much, you can't lift them, I'd probably consider a different bike if it's really that bad, but it is the cruiser version.

Most 125s are small.

[Robby]

Is this to fix a problem with the handling - like running out of suspension travel - or just for the look?

You will get a little lift - up to about 10mm - from your current shocks by increasing the preload all the way. Try that first. If you still want to replace them, I wouldn't go more than 20mm over standard. May make it a bit twitchy on the front wheel.

[Teflon-Mike]

It was interesting, looking at a YBR 'Custom' parked next to an old SR125, at the MOT mans a year or so back... you can see how the DNA evolved.... howebler....

The YBR 'custom' is the cruierified variant of the standard YBR, and to get that cruiserified 'look' a low slung stance was imperative, and achieved with a stepped seat, and I 'think' shorter rear shocks.

The very idea of fitting longer shocks, and complaining about the low seat, then SORT of suggests, you got the wrong bike, mate! Get the standard variant, it has longer shocks and higher seat and a not so low saddle, to start with... A-N-D you dont have to declare any 'mods' to the insurance company.

That's where I'd start.

My Seven-Fifty, has three-inch over-length plungers on the back, accompanied by 'Rock-Hard' ruddy springs; This is matched up front with a 1" yoke drop, stiffer 'progressive wound' springs, heavier fork oil, and a pair of narrower, lower eLCie bars... all to make it a bit more 70's 'Super-Bike', and quicken up the handling when I go play, or take the weight when I am 2-Up- touring... suits me, anyway, B-U-T....

You mention rake and trail... if you go up at the back, you rotate the whole bike around the crank-shaft; this will increase the fork rake, and hence reduce the trail, so it aught be a bit more like a sports-bike or racer, than a chopper.

How much you increase the rake and reduce trail, will depend on how much you rotate the bike about the crank, either with longer rear shocks and or fork drops. How much that will effect the 'handling' is mutable, and how much it might tolerate before it becomes dangerous is another matter still... BUT, fact that you are essentially trying to do, backwards, what Yamaha did to start with to make the 'cruiser' variant from the standard commuter model, sort of suggests that there's a lot of scope to do it.... BUT, that brings back the proposition, IF you want a higher seat and change the steering geometry... why NOT just buy the standard YBR and not have to declare the modifications to your insurance? Or buy something else altogether, with a taller seat?
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[mikeyb7]

Hi guys,

Thank you for your advice. You're right i should have bought another bike! I bought this to practice with the gears before i try and take my full test (I have a scoot for my commute to the train station) and the fact it was £350 made it a bargain. Thing is i really enjoy the gears so wanted to make it more enjoyable to ride. I'll leave it as is.

Thanks again,
Mike