cafe build — crazy T350 swingarm suggestions???

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jabcb
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cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

Being a little creative during a cold snap.

For the T350 & 2012-2019 TU250X, caster & trail are close, and the TU250X wheelbase is ~ 3” longer.
T350: 63 degrees / 3.74” / 51.2”
TU250X: 25 degrees 55 minutes / 3.62” / 54.1”

For the GT250, Suzuki eliminated the steering damper & slowed down the steering.
GT250: 62 degrees / 4” / 51.6”

Building a T350 cafe racer that eliminates the batter box, oil tank, etc …
If you add ~ 3” to the T350 swingarm , you have a bike that perhaps handles like a TU250X???

And you could get creative with the rear suspension with that extra room?
Laydown shocks or monoshock?
Would any stock Suzuki swingarms be a good starting point?
Any dirt bike swingarms (TS250, RM250, …)?
Any GS or GSX swingarms?

TU250X info:
http://www.suzukicycles.org/TU-series/i ... l~isoraami
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
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Alan H
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Re: cafe build — crazy T350 swingarm suggestions???

Post by Alan H »

I fitted a gs550 swing arm to my gt550 without mods - just take the bolt out, old out, new in and refit the same bolt. I have 13" shocks on for a bit more clearance, never did measure the shock mounts to frame bolt on either swinger. :wth:
Used the gs swinger so I could use alloy wheels and a rear disc, plus twin discs on the front too, but you probably won't need 3 discs on a 350...... :wink:
Pics & details here (again!) - viewtopic.php?f=2&t=11247&hilit=Earwig
You probably don't need a hydraulic operated clutch either - neither did I, but it annoys the purists, so why not? 8)
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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jabcb
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Re: cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

Useful tip for those wanting to use a disc on the back of a triple.
I have Redzone, which is a GT550 built by former member Coyote. It also has 3 discs. Definitely a nice bike.

Our GT250 & T500 cafe builds have a modern twin-piston front caliper & modern Nissin master cylinder. Both have stock swing arms & T500 drum rear brake.
GT250 has stock forks, Ninja caliper & modern EBC disc.
T500 has GT500 triple tree, GS750 forks, VX800 caliper & modern EBC disc.

Found some info on T20 racing. The T20 is a predecessor to the T250/T350.
Was common to add 2 inches to the swing arm length to improve handling.
So it looks like my thought process is headed in the right direction.

For the maybe-I’ll-do-it-some-day T350 build, my current thought its:
Forks from a small GS with a 2LS drum similar to the T500’s.
Longer swing arm with a T500 drum.

The 4-cylinder GS550 & 3-cylinder GT550 motors/frames are a lot wider than the T series’s. Am a bit surprised that the GS550 swing arm is a direct fit for a GT550.
There is a lot of info out there on swapping forks, but pretty much nothing useful on swapping swing arms for a narrow-framed T350.
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
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jabcb
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Joined: Mon Dec 13, 2010 4:32 pm
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Re: cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

It’s -1 degrees F. Am sipping coffee & looking at crazy ideas online. And bingo I found…

Markos’ GT250K build with a 79-80 RM/PE250 swing arm swap.
https://markosworkshop.blogspot.com/sea ... #PageNo=19

Image

Image
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
User avatar
jabcb
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Joined: Mon Dec 13, 2010 4:32 pm
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

And closer to what I was thinking, Marco used a T500 swingarm on a T250J.
Lengths axle to axle: T250 is 385mm & T500 is 505mm. That’s 120mm longer, 4.7” longer. That makes for a 55.9” wheelbase — about 2” more than what I was thinking about.
https://markosworkshop.blogspot.com/201 ... -swap.html

Image
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
dollydog
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Re: cafe build — crazy T350 swingarm suggestions???

Post by dollydog »

jab, if you're thinking of going the monoshock route, try the yzf125r like i used. see my reed valve 250 thread a bit further down. it's a lot of work, but it suits the bike and it was great fun figuring it all out :D
cheers, dd.
GTS250 road registered. TS250 engine, Ramair frame.
GT250 big bang road registered. Both pistons fire the same time. USD forks.
GT285 road registered. Overbored - 58mm and TS125 +2 pistons fitted.
GT10 road registered. '65 T10 engine, GT250 frame.
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jabcb
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Re: cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

Interesting & impressive project. How does your reed valve GT250 motor perform?
Found your topic: viewtopic.php?f=21&t=14340&p=177243&hilit=gt250#p177243

I think you have a much better selection of donor parts in the UK. I don’t think they ever imported the really small monoshock sportbikes like that YFZ125R.

The T250/T350/T500 have a pretty narrow swingarm pivot width.
Apparently doing swingarm swaps is popular enough that lists of pivot widths have been compiled. Here is one.
https://oldskoolsuzuki.info/forums/topi ... -swingarm/

I think the easiest solution is to take a T500 swingarm to a frame shop & have them shorten it.

Had forgoten about it, but some years ago I saw a T500 monoshock conversion. Was at the 2015 Cafe Racer magazine bike show.
My pics are here: viewtopic.php?f=14&t=11645&p=167181#p167181
The red 75 GT550 is Redzone.
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
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: cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

The monoshock T500 swingarm looks to be shorter than stock.

Any ideas on the swingarm donor bike?

ImageCRM_2015-08-23_T500swingarm by jabcb, on Flickr
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
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: cafe build — crazy T350 swingarm suggestions???

Post by jabcb »

Think I found it.
1982 Yamaha XS400 Seca. From the XS400 forum:
http://www.xs400.com/threads/bratstyle-1982-seca.16055/

Image
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
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