Shaving the head???
#1
08-20-2009 | 11:54 PM
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1st Gear Member
Joined: Jul 2009
Posts: 48
From: Province of Québec, Canada
Shaving the head???
Hi there!
I don't what is the exact term in english but to increase power on some engine, we sometime shave the head of the engine to reduce the chamber of combustion increasing the compression.
1. Is that possible on the klx?
2. If yes, can we combine it with a big bore?
3. Another way is to put a convexe piston to reduce the chamber of combustion... is it possible?
Eric the frenchie!!
I don't what is the exact term in english but to increase power on some engine, we sometime shave the head of the engine to reduce the chamber of combustion increasing the compression.
1. Is that possible on the klx?
2. If yes, can we combine it with a big bore?
3. Another way is to put a convexe piston to reduce the chamber of combustion... is it possible?
Eric the frenchie!!
#3
08-21-2009 | 03:27 AM
Not a backyard shed mod, unless your name is Bake.
Stick to what you know and leave the full race mods to those who race and have a factory mechanic. Squish, scavenge, overlap, maximum priming, reciprocating, all words you can Google!
The stock bike already has an 11:1 compression ratio. You'll get a small gain, if any, and I suspect effect reliability for the worse.
That being said. If your name is Tony Scott and can 'blueprint' the entire engine at the same time, then mod away.
Easier and cheaper ways to gain HP without sacrificing reliability.
Stick to what you know and leave the full race mods to those who race and have a factory mechanic. Squish, scavenge, overlap, maximum priming, reciprocating, all words you can Google!
The stock bike already has an 11:1 compression ratio. You'll get a small gain, if any, and I suspect effect reliability for the worse.
That being said. If your name is Tony Scott and can 'blueprint' the entire engine at the same time, then mod away.
Easier and cheaper ways to gain HP without sacrificing reliability.
#9
08-21-2009 | 09:34 AM
Senior Member
Joined: Oct 2006
Posts: 3,106
From: Misawa Japan
1st Gear Member
Since all I've seen is a chorus of 'don't do it,' I will attempt to at least give you some direct answers. I agree with the responses and reasoning for them, but they all assume you will use the bike as they do.
Yes, it's possible to gain performance on the KLX by increasing the compression ratio though it's not dramtic without it complimenting other mods. I have an artcle in one of my motard rags that shows how they raised the compression ratio of the 249cc jug by milling 0.4mm from the bottom of the jug for a compression ratio increacs of 0.7 (11.8:1 total). That mod alone brought a 2hp gain. It still runs off of pump gas that way, but they added the Yoshimura high cams later-on, which have greater overlap than stock thereby reducing dynamic compression ratio.
The combined effect of all of their mods is pretty amazing though. Free flow exhaust + Twin Air Filter/no lid + low friction RK chain AFAM sprocket lubed with nutech engine oil (bwahahah!!) + Yosh High Cam + the compression ratio bump-up gave them a total increase of over 9hp. Not bad!
With some of the large bore kits, your compression will already be increased to around 12:1 -Kustom Craft and BB 331 immediately come to mind- so I don't subcribe to the alarmist theories out there.
Yes, it's possible to gain performance on the KLX by increasing the compression ratio though it's not dramtic without it complimenting other mods. I have an artcle in one of my motard rags that shows how they raised the compression ratio of the 249cc jug by milling 0.4mm from the bottom of the jug for a compression ratio increacs of 0.7 (11.8:1 total). That mod alone brought a 2hp gain. It still runs off of pump gas that way, but they added the Yoshimura high cams later-on, which have greater overlap than stock thereby reducing dynamic compression ratio.
The combined effect of all of their mods is pretty amazing though. Free flow exhaust + Twin Air Filter/no lid + low friction RK chain AFAM sprocket lubed with nutech engine oil (bwahahah!!) + Yosh High Cam + the compression ratio bump-up gave them a total increase of over 9hp. Not bad!
With some of the large bore kits, your compression will already be increased to around 12:1 -Kustom Craft and BB 331 immediately come to mind- so I don't subcribe to the alarmist theories out there.
Hi there!
I don't what is the exact term in english but to increase power on some engine, we sometime shave the head of the engine to reduce the chamber of combustion increasing the compression.
1. Is that possible on the klx?
2. If yes, can we combine it with a big bore?
3. Another way is to put a convexe piston to reduce the chamber of combustion... is it possible?
Eric the frenchie!!
I don't what is the exact term in english but to increase power on some engine, we sometime shave the head of the engine to reduce the chamber of combustion increasing the compression.
1. Is that possible on the klx?
2. If yes, can we combine it with a big bore?
3. Another way is to put a convexe piston to reduce the chamber of combustion... is it possible?
Eric the frenchie!!
Last edited by tremor38; 08-21-2009 at 10:03 AM.
#10
08-21-2009 | 12:33 PM
Thread Starter
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Member
1st Gear Member
Joined: Jul 2009
Posts: 48
From: Province of Québec, Canada
See that web site, they are doing it on harley!!
http://www.nightrider.com/biketech/h...ompression.htm
The winter here in Canada is long! So I have to have a big winter projet to transform my stock 09
That is why i am asking about mill the head, domed piston, and big bore!!
but yeah i want it reliable!
And I have a good friend mecanic
Eric the frenchie
http://www.nightrider.com/biketech/h...ompression.htm
The winter here in Canada is long! So I have to have a big winter projet to transform my stock 09
That is why i am asking about mill the head, domed piston, and big bore!!
but yeah i want it reliable!
And I have a good friend mecanic
Eric the frenchie