Custom 3-1 for GT750

Getting your blazingly fast Suzuki powerplant to perform even better!

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RING_DING
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Suzuki 2-Strokes: 1974 GT750 B-4 (JDM), 1975 GT750M
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Custom 3-1 for GT750

Post by RING_DING »

Don't laugh but I got this 3-1 with a motor I bought for my project. It is custom-made from steel (heavy) and it was used in a 4-wheeler project. I was going to throw it away but decided to post here for grins. If anyone wants it they can have it for the cost of shipping, otherwise its going in the dumpster.

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1973 Suzuki GT750K with Sidecar - Bonneville 2020
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tz375
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Re: Custom 3-1 for GT750

Post by tz375 »

You know I have a soft spot for exhausts. I'll take it. Just PM me the cost.
rngdng
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Re: Custom 3-1 for GT750

Post by rngdng »

I think it's pretty cool, but I don't think it'll fit on a stock frame!!!!!



Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
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tz375
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Re: Custom 3-1 for GT750

Post by tz375 »

Good point lane.

It's only for a dyno run to see what a sled pipe with three different header pipes does compared to a Jemco and Strader 3 into 1. It will fit with a little work and a remote radiator or if necessary it can be cut and welded to point that fat pipe in a different direction.

Unless it surprises us with fantastic powers, it will not run on a street bike.
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RING_DING
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Suzuki 2-Strokes: 1974 GT750 B-4 (JDM), 1975 GT750M
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Re: Custom 3-1 for GT750

Post by RING_DING »

Sold to TZ375!
1973 Suzuki GT750K with Sidecar - Bonneville 2020
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tz375
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Re: Custom 3-1 for GT750

Post by tz375 »

It's quite light and well made. Nice welds.

Must be a sled pipe and I would guess a 2 into 1 or small triple. On second thoughts the shape looks more like a PWC. Headers are well made and the original part is also tapered which is why the headers are 1 size smaller than stock which may be a problem - among others.

Should be fun to see what it does. Lack of muffler might be an issue, so I need to zip up to AAEN in WI to pick one up.

Now to find a dyno shop a long way out of town. This could cause ears to bleed.
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RING_DING
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Suzuki 2-Strokes: 1974 GT750 B-4 (JDM), 1975 GT750M
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Re: Custom 3-1 for GT750

Post by RING_DING »

I found the muffler when clearing out the garage this weekend (completely forgot I had it). It's on its way to you.
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1973 Suzuki GT750K with Sidecar - Bonneville 2020
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tz375
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Re: Custom 3-1 for GT750

Post by tz375 »

Nice and light, like the pipe I suppose?

The three into one part is really odd with three totally different lengths. I'll run them through MOTA to see just how odd that looks. of course it could just generate the worlds widest powerband and maybe it just turns oxygen and Hydrocarbons into noise without any of that nasty power stuff that others have to worry about and manage.
D&D CHASSIS
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Re: Custom 3-1 for GT750

Post by D&D CHASSIS »

I'm thinking the latter of the two statements. ......
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tz375
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Re: Custom 3-1 for GT750

Post by tz375 »

You should see the header "design". The builder had to go with a smaller header than stock to match the tapered part of the pipe that he adapted so he sleeved the pipes at the flanges to get a nice stepped header design - but in reverse. That will most likely reduce the effective area event further.

Should make for great low end power and should stop silly people from trying to make it rev too high. :? :lol:

I have a car that does a great job of turning fuel into exhaust and supposedly makes 300 HP but it takes all of those just to get out of its own way. I don't need a bike that's just as effective....

I did get an OMAR's JEMCO three into 1 to check out and the collector design is too open and it has the headers pushed in to make fabrication easy and must restrict any pressure waves traveling back to any cylinder. Is there a decent 3 into 1 design for a bike anywhere?
D&D CHASSIS
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Suzuki 2-Strokes: GT750 dragbike
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Re: Custom 3-1 for GT750

Post by D&D CHASSIS »

To answer your question No!
rngdng
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Re: Custom 3-1 for GT750

Post by rngdng »

The TC 3 into 1 I've seen was about the best design so far, and it topped out at 6500.


Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
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tz375
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Re: Custom 3-1 for GT750

Post by tz375 »

I ran some data through MOTA over the weekend and the results were much as might be expected for a simulation.

Left center and right pipes resonate at very different engine speeds. I have not tried to work out when those waves arrive in different cylinders to see what it all means, but it looks like the powerband should be really phat......... :roll:
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