Register Community Calendar Today's Posts Search

Go Back   GZ 250 Forums > GZ250-Specific > Performance

Reply
 
Thread Tools Display Modes
Old 11-17-2010, 10:32 PM   #21
trykemike
Senior Member
 
Join Date: May 2007
Location: toronto ont canada
Posts: 177
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
__________________
sds4



Login or Register to Remove Ads
trykemike is offline  
Reply With Quote
Old 11-18-2010, 01:36 AM   #22
Water Warrior 2
Senior Member
 
Join Date: Dec 2006
Location: Squamish B.C Canada
Posts: 11,409
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.
Water Warrior 2 is offline  
Reply With Quote
Old 11-18-2010, 04:14 AM   #23
PhyPhoestilic
Junior Member
 
Join Date: Oct 2010
Location: Perris, CA
Posts: 15
Re: Engine Swap???

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



Login or Register to Remove Ads
PhyPhoestilic is offline  
Reply With Quote
Old 11-18-2010, 07:38 PM   #24
dentheman
Senior Member
 
Join Date: Apr 2010
Location: Lubbock, TX
Posts: 629
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.
__________________
2007 Shadow Spirit 750
dentheman is offline  
Reply With Quote
Old 11-18-2010, 10:52 PM   #25
Water Warrior 2
Senior Member
 
Join Date: Dec 2006
Location: Squamish B.C Canada
Posts: 11,409
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.



Login or Register to Remove Ads
Water Warrior 2 is offline  
Reply With Quote
Old 11-20-2010, 01:18 PM   #26
RamAir
Senior Member
 
Join Date: Aug 2009
Location: Toronto Canada
Posts: 165
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?
RamAir is offline  
Reply With Quote
Old 11-20-2010, 05:50 PM   #27
blaine
Senior Member
 
blaine's Avatar
 
Join Date: Feb 2010
Location: P.E.I. Canada
Posts: 3,784
Re: Engine Swap???

I would think it would drop mileage somewhat .I think a re jet would be all that is required.
:cool: :biggrin:
__________________
If at first you do succeed, try not to look surprised.


blaine is offline  
Reply With Quote
Old 11-20-2010, 09:47 PM   #28
dentheman
Senior Member
 
Join Date: Apr 2010
Location: Lubbock, TX
Posts: 629
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:
:??:
__________________
2007 Shadow Spirit 750
dentheman is offline  
Reply With Quote
Old 11-20-2010, 10:03 PM   #29
blaine
Senior Member
 
blaine's Avatar
 
Join Date: Feb 2010
Location: P.E.I. Canada
Posts: 3,784
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:
:??:
Sorry.Read that completely wrong the first time around. :blush: :tongue:
__________________
If at first you do succeed, try not to look surprised.


blaine is offline  
Reply With Quote
Old 10-24-2011, 03:54 PM   #30
mike69
Junior Member
 
Join Date: Oct 2011
Location: Texas
Posts: 1
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.
mike69 is offline  
Reply With Quote
Reply




Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 10:38 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.