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Old 11-17-2010, 09:32 PM   #21
trykemike
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Re: Engine Swap???

check out this link for a 300 cc upgrade kit. All the parts the gn is the same engine as the gz.

looks like a big performance boost. Maybe coupled with 16 tooth front sprocket 85-90 mph is possible.

http://cgi.ebay.co.uk/GN300-GN250-BIG-B ... 0589351554
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Old 11-18-2010, 12:36 AM   #22
Water Warrior 2
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Re: Engine Swap???

A 12% increase in HP and torque would be nice and the price is right for such a gain. A slightly higher cruising speed with stock gearing or larger counter sprocket would still leave some reserve power for hills and headwinds. Hopefully the carb would be able to keep up with the added displacement. The only other drawback for some riders might be less mileage per gallon and a slight bit more vibration.
Do it and we will all see how it works.
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Old 11-18-2010, 03:14 AM   #23
PhyPhoestilic
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Re: Engine Swap???

hopefully someone would be willing to try that kit and let us know how it goes.



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Old 11-18-2010, 06:38 PM   #24
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Re: Engine Swap???

Wouldn't installing that kit also require a new or modified carb and/or exhaust to handle the increased cc's? The air intake as well? Also the starter would have to handle the additional mass, and the crankshaft balance weights would be less effective with the mass of the larger piston, and would the stock valves allow sufficient aspiration? Too many unanswered questions, I think.
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Old 11-18-2010, 09:52 PM   #25
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Re: Engine Swap???

#1 :It might work well without other mods. The engine just may be limited to a little lower RPM because it will run out of fuel and exhaust flow capabilities. #2 :A 20% increase in displacement is quite a bit without other mods so it very well may be a gamble. There you go..........2 ways to look at it.



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Old 11-20-2010, 12:18 PM   #26
RamAir
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Re: Engine Swap???

Quote:
Originally Posted by trykemike
check out this link for a 300 cc upgrade kit. All the parts the gn is the same engine as the gz.

looks like a big performance boost. Maybe coupled with 16 tooth front sprocket 85-90 mph is possible.

http://cgi.ebay.co.uk/GN300-GN250-BIG-B ... 0589351554

First off those speeds are possible in our bikes! (I am 150lbs and have a windsheld so that kinda helps, a lot!) Most I hit was in between those numbers and that was all stock with sadel bags and luggeds!

This is sooo cool! Would the jet kit mod work with this to keep it fed? :drool:

Any edvise on anyone who has tried this?? How will it affect the mpg?
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Old 11-20-2010, 04:50 PM   #27
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Re: Engine Swap???

I would think it would drop mileage somewhat .I think a re jet would be all that is required.
:cool: :biggrin:
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Old 11-20-2010, 08:47 PM   #28
dentheman
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Re: Engine Swap???

Quote:
Originally Posted by blaine
I would think it would drop mileage somewhat .As for federal,you fail as soon as you adjust the idle mixture.Not something I would be concerned with.
:cool: :biggrin:
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Old 11-20-2010, 09:03 PM   #29
blaine
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Re: Engine Swap???

Quote:
Originally Posted by dentheman
Quote:
Originally Posted by blaine
I would think it would drop mileage somewhat .As for federal,you fail as soon as you adjust the idle mixture.Not something I would be concerned with.
:cool: :biggrin:
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Sorry.Read that completely wrong the first time around. :blush: :tongue:
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Old 10-24-2011, 02:54 PM   #30
mike69
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Re: Engine Swap???

I have rode cycles for 35 years,then hurt my back and went thru several operation.Now time to start riding again.I bought a 99 GZ that does not run for $200.Really clean bike.Also bought a 99 DR 650 that is wrecked but runs great.Now time to see if I can redneck them together.I really just want to do an engine swap but space is limited as yall know.Good thing I have a torch and welder.Dont know how this is going to work yet.Havent got the bikes side by side yet to put tape measures on them.Hopefully will have them both home by this weekend.Yall wish me luck and I will post picks if I can figure a way to make this work.
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