The road to over 100hp- easy enough with a GT 750?

Getting your blazingly fast Suzuki powerplant to perform even better!

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water cooled
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by water cooled »

Patience John..... we need to finish fitting the new pipes first. (The dyno results so far were performed first with JEMCo, then with straight pipes to prove the new design). We need to adjust the PJ and MJ once more, then test a new timing curves so there's just a little bit more work to do, but again, the number that counts is ET.

Once its all set, we'll print the last dyno test and then take the bike to the track. So far, the actual ET/MPH time slips seem to back up the RWHP figures for that particular configuration.
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by ja-moo »

water cooled wrote:Patience John..... we need to finish fitting the new pipes first. (The dyno results so far were performed first with JEMCo, then with straight pipes to prove the new design). We need to adjust the PJ and MJ once more, then test a new timing curves so there's just a little bit more work to do, but again, the number that counts is ET.

Once its all set, we'll print the last dyno test and then take the bike to the track. So far, the actual ET/MPH time slips seem to back up the RWHP figures for that particular configuration.
:P :P :P Would love to see them all............... :up:
Visiting from the "K" camp...........
cruisingram
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by cruisingram »

Have since moved to Hawaii- shipping all my bikes over here in a couple months- will be revisiting this again!
elbert
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by elbert »

The guys at Ebos in Sweden are working on a GT750 engine for a customer who wanted the most powerfull street GT750 in the world... Will be interesting to see the end result...

Some pictures in this link:
http://ebos.se/2stroke.asp
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water cooled
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by water cooled »

Mine is currently putting out 122.5 RWHP at 8560 rpm with a piston port design. 79.5 fl-lbs peak. Im not sure what rear tire they would select but thats a good bit of HP to put to the ground. I am very interested in seeing what they come up with.
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tz375
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by tz375 »

This should be interesting. Most powerful STREET bike eh. I wonder what their target is?
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by Suzukidave »

Hummm .. looks a lot like my motor :shock:
the older i get the faster i was
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by cruisingram »

So is there somewhere in the US that I can ship my motor off to and have it come back with 100+ hp?
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tz375
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by tz375 »

Dave,
Yours has more port area and should make more power than that Ebos motor - nice port job though.

Cruising,
That's not too hard. You need two crates. One for the motor and the other for the cash.
You are looking at a complete motor rebuild, programmable ignition, reed conversion and custom pipes plus bigger carbs and a welded and machined head with new combustion chambers. Plus you want straight cut primary gears and a crank rebuild. That should do it.
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by cruisingram »

tz375 wrote:Dave,
Yours has more port area and should make more power than that Ebos motor - nice port job though.

Cruising,
That's not too hard. You need two crates. One for the motor and the other for the cash.
You are looking at a complete motor rebuild, programmable ignition, reed conversion and custom pipes plus bigger carbs and a welded and machined head with new combustion chambers. Plus you want straight cut primary gears and a crank rebuild. That should do it.
Fair enough- lets not go for the 122hp motor, just the most you can get with a reasonable build- what hp would you expect? Some light head work, good pipes, maybe even some better carbs- not the "SKY IS THE LIMIT" build, but something just south of that?
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by Suzukidave »

Looking closer you can see where Ebos made the mod to the top case transfer area like Kevin has to his .. i wish i had done that instead of just smoothing things up .
the older i get the faster i was
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by water cooled »

If you are serious....this would give you a reasonable idea on cost to get there.
If you want 100 bhp (crank HP not RWHP):

JEMCo 3-3 Exhaust $575
(3) 36mm Mikuni $300-400
Cometics Spacer (under the block) $50-75
Cometics Copper head gasket $50
Squish head conversion $350-450
Port Block $500-600
Deck the Block $125
Motion Pro Throttle Cables $75
Jets $50-60

Misc: To get 100+ BHP you will move up considerably on the rpms so you also need to consider the following:
Crank Rebuild $450-650
New Seals
Balance rods
Balance pistons and pins

Shipping Cost to Hawaii: $800-1500 approx.

This would give you a very exciting street bike that will still pull hard down low, retain the mid and give a strong top end. There may be other ways to achieve...this is just one suggestion. This can be done is phases over time but unless you are ready to drop $3k plus....

Providing the names of people that are very good and know what they are doing is the easy part....you just need to decide how much you want to commit
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tz375
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by tz375 »

Kevin, that's a pretty good start. Add in a strip, clean, inspect , rebuild and that adds another $500 plus assuming that everything is actually OK.

Dave,
That Ebos motor is almost stock compared to your ports. I do like their twin boost ports but believe that they point in the wrong direction and will be less than optimal, but it will be interesting to see if the swirl approach will work. It might. The quality of their work looks amazing. What will make or break the 100 barrier on that project will be the reeds and carbs they choose plus the exhausts.

We know that the "simple" change of pipes from Jemco to custom is worth around 20hp if it is already ported for big pipes. We also know what reeds and boost ports are worth to power and the powerband. Did you notice the extra area that ebos are trying for on the rear of the transfers?

Bigger bores plus new sleeves would be an improvement too. We know that Polaris XCR800 are almost a drop in but they are very heavy and are taller so a spacer is needed just to get back to zero deck height.
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by cruisingram »

Well, that is a do-able list, except I can save a lot on shipping from what you have there, as long as the builder is in the USA. costs me about 100 bucks each way to Oregon. And an additional 100 dollars round trip anywhere in the USA- freight forwarders. My Oregon connection ships air cooled car and airplane motors all over the US. So at least I have that :D

four to six months before my container arrives, so have plenty of time to think about it. I want the motor done before I even get started on the rest of the bike-build.

History- on this bike- my brother owned it since I was 10 years old (he is 11 years older than me) and would pick me up from school on it (back then, riding on the back of a bike wasn't considered gay either LOL) and had it up to 135 (indicated) and the seals went out in 1980. There was no machine ship in Alaska that could re-do them. So my brother pulled the motor and sent it to Lousiana. had the seals done then, then was shipped out on ordered to Korea for 3 years. and the bike went into storage- in pieces- but all there- including the exhaust and such. Only thing missing is one radiator side cover. Year before last, he gave me the whole thing- over 20 years in storage, and it was a literal squirrels nest, with mushrooms and pinecones in everything- but the motor was still pristine looking, wrapped in three plastic engine-storage bags. So now I have a 1973 GT 750 that I have some really fond memories of from my childhood and wondering how far I want to take this thing.

I am opening a bike shop here in Hawaii as soon as my container arrives- but I am the first one to tell you that I am not a two stroke expert. So, I am hoping this bike helps me with that learning curve. I don't know if I will try to sell it after I ride it for a while or keep it forever- depends on how much I spend on it and how big an offer I get on it- though, I could fall in love with it again too LOL

Oh- links to Ebos etc?
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Re: The road to over 100hp- easy enogh with a GT 750?

Post by titan performance »

I guess it's time to dust this off and get it out again, in case some of you boys haven't seen it.
This bike is the work of a friend of mine, who built the frame, and has been working on the bike for the past 15 years or so.
It's got a big bang motor...well sort of. He has changed the firing order so that the outer 2 pots fire together. He did this because the chambers needed would not fit under the motor, but with the outer cylinders sharing a pipe...the 2 fit nicely.
I have no proof, but he reckons it puts out 125 bhp. and pulls cleanly and strong right through the range.
Click on this link for more pics.

http://www.flickr.com/photos/suzuki_gt5 ... hotostream" onclick="window.open(this.href);return false;
Keeping old 2 strokes alive !
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