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								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
											My Bike:  yz490 
												Location:  Bristol 
							
						
		 
		
						
						
													
							
						
									
						Post 
					 
								by jackdim   »  Thu Jul 16, 2009 5:59 pm 
			
			
			
			
			Noticed a difference in the piston's I took out of my bike and the pistons that I bought from Kawasaki when I got them home, are they interchangable and what's the purpose of having two different types? 
Old Pistons (marked 707 with a flat top):
 
New Pistons (marked 657 with a ridged top): 
 
Comparison:
 
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
								RedexRobB 							 
						Site Admin 			
		Posts:  7212 		Joined:  Fri Aug 30, 2002 7:37 pm 		
		
											My Bike:  ZXR400L3 
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						Post 
					 
								by RedexRobB   »  Thu Jul 16, 2009 6:20 pm 
			
			
			
			
			No idea, but thats pretty damn interesting that they are different!!
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
								masterofinsanity 							 
						Site Admin 			
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						Post 
					 
								by masterofinsanity   »  Thu Jul 16, 2009 8:09 pm 
			
			
			
			
			did you order the correct year piston?
			
			
									
									Don't forget people there is more to the zxr400 than this forum... check out 
www.zxrworld.co.uk  also.
 
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
											My Bike:  yz490 
												Location:  Bristol 
							
						
		 
		
						
						
													
							
						
									
						Post 
					 
								by jackdim   »  Thu Jul 16, 2009 8:59 pm 
			
			
			
			
			Yup, ordered them for the L3 which is the year of my chassis but not sure if the motor is from a different model zxr400?
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
								RedexRobB 							 
						Site Admin 			
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						Post 
					 
								by RedexRobB   »  Thu Jul 16, 2009 9:08 pm 
			
			
			
			
			Wouldnt count that out.. May have been better to supply an engine number.
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
											My Bike:  yz490 
												Location:  Bristol 
							
						
		 
		
						
						
													
							
						
									
						Post 
					 
								by jackdim   »  Thu Jul 16, 2009 9:12 pm 
			
			
			
			
			RedexRobB wrote: Wouldnt count that out.. May have been better to supply an engine number.
Agreed, will chat to the suppliers tomorrow and see what they say.
 
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
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						Post 
					 
								by jackdim   »  Fri Jul 17, 2009 3:23 pm 
			
			
			
			
			So then! I found both pistons are for an L3 but one is for a UK L3 and the other is for a Japanese L3, two different part no's. I didn't have time to check but my friend at the dealershop is going to check that the UK and Japanese L3's: Cylinders, Cylinder Head, Cams, Valves, Conrods, Crank etc are the same by comparing part no's and if so they're interchangable and I'll use them.
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								zimm 							 
						zxr400 oc member 			
		Posts:  2320 		Joined:  Tue Oct 10, 2006 12:32 am 		
		
											My Bike:  ZXR400-M4, ZX4, ZX6R. 
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						Post 
					 
								by zimm   »  Fri Jul 17, 2009 3:58 pm 
			
			
			
			
			looks like the UK spec ones would give a higher compression ratio ..
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
											My Bike:  yz490 
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						Post 
					 
								by jackdim   »  Fri Jul 17, 2009 4:07 pm 
			
			
			
			
			Perhaps the 707's which came out the bike are designed for slightly lower comp for lower power to be line with Jap restrictions of bikes at the time?
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								zimm 							 
						zxr400 oc member 			
		Posts:  2320 		Joined:  Tue Oct 10, 2006 12:32 am 		
		
											My Bike:  ZXR400-M4, ZX4, ZX6R. 
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						Post 
					 
								by zimm   »  Fri Jul 17, 2009 4:14 pm 
			
			
			
			
			maybe ... they look the same as the ones in my H engines ... I'll check the part numbers later.
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
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						Post 
					 
								by jackdim   »  Fri Jul 17, 2009 4:17 pm 
			
			
			
			
			spot on, thanks. 
 
Unless I'm absolutely certain that there is no difference between the Jap and UK L3 motors (other than pistons) I think I'll most likley stick to the ones that came out of the bike, any difference in power between the two is probably so marginal I'd probably hardly notice it on the road.
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								tk400 							 
									
		Posts:  222 		Joined:  Thu May 26, 2005 10:50 am 		
		
											My Bike:  ZXR400 , ZXR950 
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						Post 
					 
								by tk400   »  Sun Jul 19, 2009 4:40 pm 
			
			
			
			
			If you don't use them. how much do you want for them..cheers. 
 
Regrds TK400
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
											My Bike:  yz490 
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						Post 
					 
								by jackdim   »  Sun Jul 19, 2009 5:26 pm 
			
			
			
			
			Not for sale, exchanged the 657s for 707s free of charge.
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								zimm 							 
						zxr400 oc member 			
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											My Bike:  ZXR400-M4, ZX4, ZX6R. 
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						Post 
					 
								by zimm   »  Sun Jul 19, 2009 6:34 pm 
			
			
			
			
			sorry for the delay 
 
checked my box of pistons ..  
 
all are marked 657.. all came out of H model engines 
 
I have heard about some import L's circa L3/L4 that had lower compression and milder cam profiles.. looks like yours is one 
 
tbh, if you can.. i'd swap them back and fit the 657's to gain a touch of compression.  
 
might be worth checking out any differences with your cam's aswell.
			
			
									
									
						 
		 
				
		
		 
	 
				
		
		
			
				
																			
								jackdim 							 
									
		Posts:  135 		Joined:  Tue Jul 14, 2009 12:29 am 		
		
											My Bike:  yz490 
												Location:  Bristol 
							
						
		 
		
						
						
													
							
						
									
						Post 
					 
								by jackdim   »  Sun Jul 19, 2009 11:56 pm 
			
			
			
			
			I'll see if I can get the 657s back, they've got to be interchangable with the 707s eh? 
 
I need to strip the motor out of my UK L1, might use the cams out of that for my L3....