1972 GT550 cafe build - new topic

Retro, Wild, Cafe, etc. The stuff only your imagination can come up with.

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jabcb
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Re: 1972 GT550 cafe build - new topic

Post by jabcb »

Installing the Accent ignition. Very easy to install. There is a good blob of something to protect a few of the components from vibration.

The replacement cam has two magnets & the specs list the dwell angle as 120 degrees. The stock ignition has a dwell angle of around 180 degrees, so the Accent ignition should use less current the stock points.

Imagecafe-GT550-1233 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
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Alan H
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Re: 1972 GT550 cafe build - new topic

Post by Alan H »

If there's only 1 pickup and 2 magnets, it's for a twin, not a triple. It either needs three pickups with 3 12v coils and one 'target', or three targets (magnets or optical triggers), one pickup and three 4v coils connected in series.
2 magnets and 1 trigger will spark every 180 degrees, not every 120 degrees as you need for 3 cylinders.

I think you may be mistaking dwell angle for firing interval.

Unless of course, it's a completely new system that hasn't been discussed yet, in which case, please carry on and post more details.
The old system was for the 380 and 750 Suzies and kwak triples. Wasn't it to do with engine rotation?
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: 1972 GT550 cafe build - new topic

Post by jabcb »

The circuit board has 3 pickups 120 degrees apart & is labelled for the “GT 55?”. (The “?” is hidden behind the white sticker.) The replacement cam is labelled “Suzuki GT”.
The manual claims the dwell angle is 120 degrees.

I’m certainly no expert, but this is guess…
The cam has two closely-spaced holes. One is empty & the other has a magnet. 180 degrees away from that pair of holes are another two holes with one empty & one with a magnet.
If this is a north pole + south pole arrangement then the dwell angle of around 120 degrees is span from the magnet in one pair to the hole in the other pair.
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: 1972 GT550 cafe build - new topic

Post by Alan H »

I see now. I think I'll stick to points though!! :lol:
Think of how stupid the average person is, then realise that half of them are more stupid than that.
cobraace
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Re: 1972 GT550 cafe build - new topic

Post by cobraace »

Great work looks sharp :clap: what did you do with the JR chamber's that are on the first picture.
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jabcb
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Re: 1972 GT550 cafe build - new topic

Post by jabcb »

I had offered the pipes at a hard to beat price: shipping cost + $1. Got no serious interest other than the garbage man, who hauled them away some time ago.

Also offered the fugly fairing & got no interest. Had it stored in a friend’s garage. He moved & its now gone but I don’t know what he did with it. Might have ended up being used for target practice.
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
cobraace
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Re: 1972 GT550 cafe build - new topic

Post by cobraace »

jabcb wrote:I had offered the pipes at a hard to beat price: shipping cost + $1. Got no serious interest other than the garbage man, who hauled them away some time ago.

Also offered the fugly fairing & got no interest. Had it stored in a friend’s garage. He moved & its now gone but I don’t know what he did with it. Might have ended up being used for target practice.
Sorry I miss it :(
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jabcb
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Re: 1972 GT550 cafe build - new topic

Post by jabcb »

Project nearing completion.

From scratch wiring just about done. Using new rectifier & regulator from Oregon Motorcycle Parts, CustomLED LED flasher & GS-series starter relay. Using relay to connect regulator directly to the battery.
Imagecafe-GT550-1352 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
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jabcb
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Re: 1972 GT550 cafe build - new topic

Post by jabcb »

Wiring done. Just a few little tasks left.
Imagecafe-GT550-1369 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
Zunspec4
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Re: 1972 GT550 cafe build - new topic

Post by Zunspec4 »

Wow, that's looking super sweet, jabcb 8) 8) 8) :up:

Cheers Geoff
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Evans Ward
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Re: 1972 GT550 cafe build - new topic

Post by Evans Ward »

What a beauty! :clap: Can’t wait to see the completed project!
1976 Suzuki GT750 (Maui Blue), 1972 Kawasaki H2 750 Mach IV (Candytone Blue), 1984 Yamaha RZ350 (KRR- Yellow/ Black).
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joolstacho
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Re: 1972 GT550 cafe build - new topic

Post by joolstacho »

Super-tidy mate, well done. :clap:
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jabcb
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Re: 1972 GT550 cafe build - new topic

Post by jabcb »

Using angled tapered K&N filters. Outer filters need to be rotated to clear early side covers. But then the right filter contacts the oil pump cover — problem easily solved by removing part of the cover.
Imagecafe-GT550-1449 by jabcb, on Flickr

Am now done except for the mirrors and Higgspeed exhaust.
Imagecafe-GT550-1450 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
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Posts: 4241
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: 1972 GT550 cafe build - new topic

Post by jabcb »

Higgspeed exhaust is here.

Turns out that there is a small difference between early & late frames. Not as big as was with the GT380 build. Practice makes perfect.

Looks like designing a side stand that doesn’t mess with cornering clearance is going to be more of a challenge that on the GT380.
Trial adapter for the left exhaust:
Imagecafe-GT550-1506 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
Alan H
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Joined: Thu Feb 16, 2012 11:50 am
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Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
Location: The Republic of South Yorkshire

Re: 1972 GT550 cafe build - new topic

Post by Alan H »

Very nice. I do love the Gold GT550 J.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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