Is this safe?

jammer415

Been Around the Block
CB500T

I noticed on this build that the rear shock is not mounted directly to the swing arm mount like its suppose to, but somehow mounted to part of the hub? Or the mounting bolt for the rear brake?

Is this ok to do? (Aside from lowering the bike and potentially bottoming out)

Is this safe to do? If no, why not?


(Added extra photo of another 500T as reference)
 

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Looks like some kind of lowering blocks are bolted in? They were common in 1970's but were usually only about 2~3" long, those are probably home made and 5"6" long. They work but personally I don't like them mor even the idea of them. There will always be people willing to make and sell stuff with dubious safety
 
Ya here is the actual build post link, it does mention plans of “removing lowering kit”, seems like it was left in after all.

http://vintage-and-classic-honda-s.456789.n3.nabble.com/1976-Honda-CB500T-Brat-Project-td4062231.html

Why don’t you like the idea of them?

And ya the angle of the shock is way different... Would it be better/safer to just install shorter shocks to lower the bike?
 
It would be much better to install shorter shocks, as long as they are sprung for the weight of bike and rider.
 
irk miller said:
Plus, the angle of the shocks will stiffen up the ride.

Won’t they make the ride softer?
The Wheel creates force vector (0,10) assuming the SA is level at this moment
But the shocks are at an angle, So they need to produce a force vector (x,-10).
If the shocks are at say 45* then the resulting force vector from the shocks is a (-10,-10) the total magnitude of which is just over 14.1
So those shocks see 41% more load at that angle VS a vertically mounted set.
 
In the most simple of terms, it's a bad idea. It changes overall frame geometry. May be good may be bad but without measuring, it's a bad idea. Changes shock loading. Overall effect can't be good, but how bad is it, who knows. It's just a dumb idea.

Most importantly, if the struts/extensions/lowering kit is not secured in all planes, it will seriously impact the way the rear suspension works. All in all, it's a dumb idea and poor way to do things. I would recommend going back to stock suspension and work from there.

Not sure that a cheap brat style seat is an improvement on the looks of that thing, but back in the day no one loved a CB500T. They were just butt ugly bikes. So maybe it's an improvement in looks if you like that sort of thing.
 
farmer92 said:
Won’t they make the ride softer?
The Wheel creates force vector (0,10) assuming the SA is level at this moment
But the shocks are at an angle, So they need to produce a force vector (x,-10).
If the shocks are at say 45* then the resulting force vector from the shocks is a (-10,-10) the total magnitude of which is just over 14.1
So those shocks see 41% more load at that angle VS a vertically mounted set.

Yeah, you're right. I had it backwards. As you angle the shock, it essentially moves the load to spring and takes away all the damping. You would need twice as heavy of a spring for such a change in angle.
 
Ya it didn’t seem right to me either... Which is why I asked here. I reached out to the builder too, but haven’t gotten a response. Lower shocks just seem like the way to go.

Either way thank you everyone for chiming in with feedback

And what’s wrong with the 500T looks?? Or do I just have the same taste in bikes as I do in women... Butt ugly with big seats! ;D
 
I think the seat/side cover design is the big issue with the 500t. Teazer has expressed more than once his disdain for brown seats. LOL. The tank is actually really sought after for cafe bikes because of its shape and knee dents.
 
Oddly enough, that seat works well with the overall color scheme. But I can't really admit that or else someone will accuse me of flip flopping. BTW did I mention that I don't like brown seats on bikes. LOL
 
Haha Honda had to offset making the best tank ever put on a bike by mating it to the worst seat ever put on a bike lol (All of which are in my own opinion and therefore do not really matter)

Sent from my SM-G920V using Tapatalk
 
Yeah, like a Camry with a ground effects kit and rims...
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Ok so oem rear shock height is 12.5” (320mm), ya?

So if one were to want to lower a CB500T a bit... Does anyone have experience with any after market shock options?

TEC? Emgo? Hagon?

Would 290mm bottom out on bumps if the fender is gone, but the frame unchopped?
 
It depends on spring rate and shock travel. If you only had 50mm travel you could probably use 270mm shocks, but, you will probably get closer to 75~80mm travel. Easiest thing to do is put bike on centre stand, remove both shocks then lift wheel until it contacts a fixed point (frame) Measure distance between shock mount bolts and add at least 15mm (or drop wheel 1/2" from frame before measuring) That will give you length of compressed shock. all you need then is to find amount of travel and add it to the measurment you have for total extended length. It's actually much easier to do then to try and explain
 
Ohh ok I see... So if I’m using 290mm shocks (as reference) and assuming 80mm of compression depth... That distance measured cannot exceed 210mm (ideally 1/2 inch additional space).

I know there are some adjustable shocks out there, but haven’t seen any below 320mm... so I’ll have to shop around.
 
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