Dirty grease bike needs some love

Zeldanumber17

New Member
Oct 26, 2019
19
8
3
21
This thing has about 5000 miles on the motor and bike aside from the rear wheel being swapped 3 times from spokes breaking. The engine is starting to get tired and not rev like it used to as well as less power.

What things do I need to look for to know which type of piston and jug I need to get? I know I have a 40mm intake port. Or would a set of new rings suffice? There isn’t scoring on the cylinder walls.


This is the bike. Used to commute 15-20 miles a day.
https://m.imgur.com/tIKG6bz
 
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indian22

Well-Known Member
Dec 31, 2014
3,826
4,556
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Oklahoma
5 k and down on power. Sometimes it's just the spark plug cheap solution, but if that's not it then It's time to decoke both head and piston...pull both and get the piston top and combustion chamber all shiny again. This really helps restore power. While it's apart get a copper head gasket, rings, wrist pin and bearing, NGK spark plug, air cleaner and fuel filter and fuel line. If the compression was down the rings and gasket should bring it back up to spec. I'm going by what you've told us so this is really just top end maintenance and replacement of consumables. If you decide to replace the jug order one like you have if it suited you before and don't forget the base gasket of the same thickness to keep port timing the same. My GT 5 engines got a lot more miles than 5k on the cylinder and rings and still runs fine.

Understand that when you ask a question about a problem the answer has to be very general in nature, not like being there and fixing it ourselves. These are things I do if I feel the engine is tired, and usually the motor runs much better, but no always and when that's the case the solution lies somewhere else. Work bike really needs to be dependable.

Good luck,

Rick C.
 

indian22

Well-Known Member
Dec 31, 2014
3,826
4,556
113
Oklahoma
5 k and down on power. Sometimes it's just the spark plug cheap solution, but if that's not it then It's time to decoke both head and piston...pull both and get the piston top and combustion chamber all shiny again. This really helps restore power. While it's apart get a copper head gasket, rings, wrist pin and bearing, NGK spark plug, air cleaner and fuel filter and fuel line. If the compression was down the rings and gasket should bring it back up to spec. I'm going by what you've told us so this is really just top end maintenance and replacement of consumables. If you decide to replace the jug order one like you have if it suited you before and don't forget the base gasket of the same thickness to keep port timing the same. My GT 5 engines got a lot more miles than 5k on the cylinder and rings and still runs fine.

Understand that when you ask a question about a problem the answer has to be very general in nature, not like being there and fixing it ourselves. Since you didn't mention any other issues like hard to start, missing badly etc. I have to assume it's as you said just down on power. These are the things I first do if I feel the engine is tired, and usually the motor runs much better, but not always and when that's the case the solution lies somewhere else. A work bike really needs to be dependable.

Good luck,

Rick C.
 

Zeldanumber17

New Member
Oct 26, 2019
19
8
3
21
5 k and down on power. Sometimes it's just the spark plug cheap solution, but if that's not it then It's time to decoke both head and piston...pull both and get the piston top and combustion chamber all shiny again. This really helps restore power. While it's apart get a copper head gasket, rings, wrist pin and bearing, NGK spark plug, air cleaner and fuel filter and fuel line. If the compression was down the rings and gasket should bring it back up to spec. I'm going by what you've told us so this is really just top end maintenance and replacement of consumables. If you decide to replace the jug order one like you have if it suited you before and don't forget the base gasket of the same thickness to keep port timing the same. My GT 5 engines got a lot more miles than 5k on the cylinder and rings and still runs fine.

Understand that when you ask a question about a problem the answer has to be very general in nature, not like being there and fixing it ourselves. These are things I do if I feel the engine is tired, and usually the motor runs much better, but no always and when that's the case the solution lies somewhere else. Work bike really needs to be dependable.

Good luck,

Rick C.
Thank you for the tips. I had just replaced the spark plug. but I have a new set of rings and gaskets on order and when they come I will clean the combustion chamber as well. I’ll let you know how it goes. Cheers
 
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