GT380 + Higgspeed + sidestand question

[jabcb]

GT380 mix-and-match project I’ve had for a few years.
72 frame + 74 motor + 74-77 Higgspeed.

For the 74-77 models, Suzuki made changes to the frame + exhaust for more cornering clearance.
So I have the early frame, and the late motor+Higgspeeds.
Have little adapter plates to attach the exhaust to the frame.

So far I’ve put a plate between the sidestand bracket & frame — this eliminated an interference between the bracket & exhaust.
Also going to try a GT550 stand.

Am wondering how well the sidestand fits when you have a matching set of 74-77 frame+motor+Higgspeed.
And what people have done to improve cornering clearance.
Some pics would help too.

[jabcb]

Tried a 72 GT550 stand. It improved the cornering clearance a little.
A T500 stand looks like it might be another possibility.

Have a solution that just requires a little fabrication & welding. (Neither of which I can personally do.)
The Higgspeeds are upswept.
So if you lower the stand pivot point & change the pivot angle, you can use a longer stand.
Wouldn’t have to move the end back much so that its in the upswept area.
This could possibly totally eliminate any cornering clearance penalty for having a sidestand.

[jabcb]

Interesting headway.

Tried a TS100 sidestand. It bolts up to the stock GT380 bracket.
Its straight & folds up behind the exhaust. But its a little too long.

I have the forks compressed a bit with tiedowns.
Looks like the TS100 sidestand might be close to OK with uncompressed forks & 320mm long shocks. (Stock shocks are 300mm long.)

The TS100 sidestand doesn’t have a tang for your foot, so that would have to be weld on.

A little more experimenting & I might have a solution.

[jabcb]

Look to have a workable solution.

1974 TS100 side stand + GT250 bracket + a spacer.
Its a bit precarious & should lean over a bit more. Longer shocks might resolve this.
The actual gap between the stand & exhaust is a bit larger that it looks in the second pic.

[jabcb]

Two more pics.
Looks clean from the side. The frame centerstand bracket acts as the sidestand stop.
Will require some figuring to design the tab used to lower/raise the stand.

[Vintageman]

Good job. Yeah wouldn't want it to tip over. Nice bike. How do like the way those pipes work if you had a chance to try them.

Can you add a picture showing the pipes on the back half of bike?

Mike

[jabcb]

Had thought about getting early-model pipes & selling these Higgspeeds. But I’m trying to keep this a low-cost tinkering project.

I have the motor to the point it starts easily & runs well, but I haven’t ridden it yet.

I’m using white HDPE plastic for the exhaust adapter plates & sidestand spacer. Its cheap & easy for me to work with.
Am set on the adapter plate dimensions for the two outer cylinders. Need to decide on the length of the center adapter plate & spacer thickness.
Will have the parts water jet cut when I have them figured out — then I’ll be ready for a test ride.

I have the outer pipes positioned roughly where they are in the pics of late model GT380s with Higgspeeds. The tops of the pipes are roughly aligned with the lower shock nuts. And there is plenty of lateral clearance to allow for longer shocks.

I’e decided on 320mm shocks. Am going to use a spare T500 rear wheel that I have. So I’m looking at raising the rear end around 30mm when parked. (20mm for shocks & 10mm for larger rear tire) That should fix the sidestand lean problem & might allow for a smidgen thicker spacer.

Will post more pics when I have them.

[jabcb]

This might help on other projects…

Getting this to work is a game of tenths of inches. One spot where its easy to get .1” is the bolt+nut attaching the sidestand.

The GT380/GT550/GT250/… attach the sidestand with bolt 09100-10067 & a nut. The bolt is 30mm long.
The TS100 attaches the sidestand with bolt 09100-10287 & J-washer 09169-10008. The bolt is 27mm long.

The J-washer is NLA but is available via eBay, or you could make your own.

[jabcb]

Pic from rear as requested. (Only working on left side for now.)

Bike has 20mm added to shock, TS50 sidestand, GT380 bracket & a sidestand spacer.
The TS50 & TS100 side stands are pretty much the same except the TS50 version is shorter.

[jabcb]

Another pic from the rear.

Upgraded to a T500 rear wheel with a 2.15-18 rim + an Avon 110/90-18 tire.
Have 20mm added to the shock, TS50 sidestand, GT250 bracket & a sidestand spacer.
Am close to the final setup.

Also have a test fit of a Lucas aftermarket taillight.

[Alan H]

Put slightly longer shocks on or even a 19" rear rim.
I had a bigger rim on my 550 back in '72 and it made cornering far better.
Looks like I need slightly longer shocks on my current 550 as I can't upsize alloy GS wheels.

[jabcb]

Put slightly longer shocks on or even a 19" rear rim.
I had a bigger rim on my 550 back in '72 and it made cornering far better.
Looks like I need slightly longer shocks on my current 550 as I can't upsize alloy GS wheels.

I picked up 20mm with longer shocks + 10mm with the larger rear tire.

The RedZone GT550 is fine for the type of riding I do. It has Bassani chambers + longer shocks + slightly oversize tires.

My gray GT750 has another solution: 3-into-1 exhaust.

[jabcb]

Settled on a final setup that has no impact on cornering clearance.

Using a T500 sidestand bracket. Redrilled the bracket mounting holes to shift the stand closer to the center of the bike.
Using a TS250 sidestand and 1/2” thick spacer.
No additional stop is needed. Will need to have a tab welded on to raise/lower the stand.

Pic in the up position:


The stand is behind the exhaust & just enough sticks out so that a tab can be welded on:

[jabcb]

Repost of pics in this topic. Old links were in Photobucket & new links are in Flickr.

First option: 1974 TS100 side stand + GT250 bracket + a spacer.
GT380_0501 by Bob Haberstroh, on Flickr
GT380_0503 by Bob Haberstroh, on Flickr

GT380_0506 by Bob Haberstroh, on Flickr
GT380_0507 by Bob Haberstroh, on Flickr

Second option: Bike has 20mm added to shock, TS50 sidestand, GT380 bracket & a sidestand spacer.
GT380_0511 by Bob Haberstroh, on Flickr
GT380_0521 by Bob Haberstroh, on Flickr

Final setup: Using a T500 sidestand bracket. Redrilled the bracket mounting holes to shift the stand closer to the center of the bike. Using a TS250 sidestand and 1/2” thick spacer.
GT380_0541 by Bob Haberstroh, on Flickr
GT380_0542 by Bob Haberstroh, on Flickr

More pics of final setup are here: viewtopic.php?f=21&t=13036