tips: T350/T500 forks with external springs + more preload

Getting your chassis to handle your blazingly fast Suzuki powerplant.

Moderators: oldjapanesebikes, H2RICK, diamondj, Suzsmokeyallan

Post Reply
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

tips: T350/T500 forks with external springs + more preload

Post by jabcb »

I found stock springs that might work on the early T350 & T500 forks with external springs.
They are longer & provide a good bit more preload.
Post about the springs: viewtopic.php?f=2&t=10874

For forks with internal springs, you just slide the tubes into the triple tree.
But doing this with external springs create the preload.

So does anyone have tips on how to install for fork tubes with external springs & more preload?
(It would seem obvious but I suspect someone has some tips that will make this easier.)
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
sbaugz
To the on ramp
Posts: 337
Joined: Fri Jun 19, 2015 5:14 am
Country: USA
Suzuki 2-Strokes: T500, S32-2, GT185

Re: tips: T350/T500 forks with external springs + more prelo

Post by sbaugz »

jabcb wrote:I found stock springs that might work on the early T350 & T500 forks with external springs.
They are longer & provide a good bit more preload.
Post about the springs: viewtopic.php?f=2&t=10874

For forks with internal springs, you just slide the tubes into the triple tree.
But doing this with external springs create the preload.

So does anyone have tips on how to install for fork tubes with external springs & more preload?
(It would seem obvious but I suspect someone has some tips that will make this easier.)

Maybe I'm wrong but don't you just put some washers or spacers between top of spring and under lower triple?
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: tips: T350/T500 forks with external springs + more prelo

Post by jabcb »

Maybe my question wasn’t clear.
I was asking for tips on how to most easily assemble the forks.


Using plastic plumbing pipe to add preload for internal fork springs is pretty effective because the springs are long.

But the external fork springs on the T350/T500 are much shorter — using washers can reduce fork travel because the springs can go solid. Max deflection for the T500 springs, which is around 4.7”, is the upper bound limit of preload + fork travel. Also, the springs are badly overstressed at solid height, which is why they go to mush.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Post Reply