300cc big power(30HP) 4valve low price engine

Tonywang · 01-18-2011, 03:39 AM

You can just find this big power engine in CHONGQINGDONGBEN INDUSTRY CO.,LTD OF CHINA. Any questions pls let me know,I will answer

Pls contact me,

Tony
CHONGQING DONGBEN INDUSTRY CO.,LTD
Tel: 0086 23 62453892
Fax:0086 23 62483776
Mobile:0086 13667619232

E-mail ï¼šwang72274@hotmail.com
http://www.alibaba.com/product-gs/386281035/ENGINE.html

Tonywang · 01-18-2011, 03:48 AM

300cc 4valve big power
max power:22kw/8500
max torque:25N.M/8000

Mail Structure
DOHC:auto engine tech
4-valve:more airintake,higher fuel burning efficiency
No Rocker Arm:fewer noise,less valve adjusting
Racing Power: Higher power and Higher torque
Balance Shaft:low vibration
Water-cooled

rofessional design,no overheat
Leading design Piston and Piston Ring:super resistance

E-mail ï¼šwang72274@hotmail.com

Weldangrind · 01-18-2011, 12:23 PM

I'd be curious to see that engine with the valve cover removed. I have a four valve OHC XR250R, and it has rockers. I struggle to understand how the cam acts upon the valves without rockers.

FastDoc · 01-18-2011, 01:08 PM

The cam rides right over the valves, separated by shims placed in shallow buckets. This usually requires dual camshafts.

FastDoc · 01-18-2011, 01:12 PM

Here you go!

Weldangrind · 01-18-2011, 01:13 PM

Thanks for the explanation. I've worked on OHC cars before as well, but I've never had experience with that style of setup.

FastDoc · 01-18-2011, 01:14 PM

You can see why this arrangement is necessaraly a bigger PIA to adjust.... In some cases you need to remove the cams to adjust the valves, which is done by replacing the shim. This is the case on my Gold WIng. That's a project I don't plan to do myself. That bike has a lot of valves.

Weldangrind · 01-18-2011, 01:15 PM

That pic makes it even more clear. The shallow bucket that you described looks just like a shortened version of a pushrod lifter.

ejcycles · 01-20-2011, 02:14 PM

Hi FastDoc

Honda is using the same concept {Shim & Bucket} with a single camshaft in the CRF 150 & up model racers now.

FastDoc · 01-20-2011, 02:50 PM

I wonder how they make that work. It seems to me the valves would have to be parallel which would not make for a very efficent combustion chamber shape....

Reveeen · 01-20-2011, 05:02 PM

You can thank Kawasaki for this idea. There is a special hook shaped tool you can sneak between the cam and bucket that allows shim replacement without pulling the cam(s). At high RPM sometimes the shims can get spat out causing all manner of catastrophe..... there is a "shim under" conversion that does require cam removal to adjust. Nothing like a tool box full of $5 shims at tune up time!

FastDoc · 01-20-2011, 05:11 PM

My GS750 is shim on top of buckets, and I have the tool. It's a PIA but at least do-able.

My Gold Wing is shim under buckets, and I'm not even going there.

Now that I think about it they are due for their first check, I have over 25,000 miles on it....

I like screw type adjusters, and I really appreciated my Harley's hydraulic lifters.

recracer · 02-25-2011, 09:02 PM

this engine can not be brought into the usa at this time

01-18-2011, 03:39 AM	#1
Tonywang Join Date: Jan 2011 Posts: 7	300cc big power(30HP) 4valve low price engine You can just find this big power engine in CHONGQINGDONGBEN INDUSTRY CO.,LTD OF CHINA. Any questions pls let me know,I will answer Pls contact me, Tony CHONGQING DONGBEN INDUSTRY CO.,LTD Tel: 0086 23 62453892 Fax:0086 23 62483776 Mobile:0086 13667619232 E-mail ï¼šwang72274@hotmail.com http://www.alibaba.com/product-gs/386281035/ENGINE.html
	0

01-18-2011, 03:48 AM	#2
Tonywang Join Date: Jan 2011 Posts: 7	Re: 300cc big power(30HP) 4valve low price engine 300cc 4valve big power max power:22kw/8500 max torque:25N.M/8000 Mail Structure DOHC:auto engine tech 4-valve:more airintake,higher fuel burning efficiency No Rocker Arm:fewer noise,less valve adjusting Racing Power: Higher power and Higher torque Balance Shaft:low vibration Water-cooledrofessional design,no overheat Leading design Piston and Piston Ring:super resistance E-mail ï¼šwang72274@hotmail.com
	0

01-18-2011, 12:23 PM	#3
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	I'd be curious to see that engine with the valve cover removed. I have a four valve OHC XR250R, and it has rockers. I struggle to understand how the cam acts upon the valves without rockers. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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01-18-2011, 01:08 PM	#4
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	The cam rides right over the valves, separated by shims placed in shallow buckets. This usually requires dual camshafts. __________________ Happy to serve.
	0

01-18-2011, 01:12 PM	#5
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	Here you go! __________________ Happy to serve.
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01-18-2011, 01:13 PM	#6
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Thanks for the explanation. I've worked on OHC cars before as well, but I've never had experience with that style of setup. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

01-18-2011, 01:14 PM	#7
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	You can see why this arrangement is necessaraly a bigger PIA to adjust.... In some cases you need to remove the cams to adjust the valves, which is done by replacing the shim. This is the case on my Gold WIng. That's a project I don't plan to do myself. That bike has a lot of valves. __________________ Happy to serve.
	0

01-18-2011, 01:15 PM	#8
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	That pic makes it even more clear. The shallow bucket that you described looks just like a shortened version of a pushrod lifter. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

01-20-2011, 02:14 PM	#9
ejcycles Join Date: Oct 2006 Location: 11481 State Route 44 Mantua, Ohio 44255 Posts: 1,112	Hi FastDoc Honda is using the same concept {Shim & Bucket} with a single camshaft in the CRF 150 & up model racers now. __________________ Thanks, Bruce @ Endless Journey Cycles "Phone Calls Only" ~330-274-0098~ Hours: Tue.-Fri. 10:00-6:00 Sat. 10:00-4:00 EST. Dealer for: Lifan, Crossrunner ATVs. http://www.endlessjourneycycles.net
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01-20-2011, 02:50 PM	#10
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	I wonder how they make that work. It seems to me the valves would have to be parallel which would not make for a very efficent combustion chamber shape.... __________________ Happy to serve.
	0

01-20-2011, 05:02 PM	#11
Reveeen Join Date: Jun 2009 Location: orbital platform Posts: 741	You can thank Kawasaki for this idea. There is a special hook shaped tool you can sneak between the cam and bucket that allows shim replacement without pulling the cam(s). At high RPM sometimes the shims can get spat out causing all manner of catastrophe..... there is a "shim under" conversion that does require cam removal to adjust. Nothing like a tool box full of $5 shims at tune up time!
	0

01-20-2011, 05:11 PM	#12
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	My GS750 is shim on top of buckets, and I have the tool. It's a PIA but at least do-able. My Gold Wing is shim under buckets, and I'm not even going there. Now that I think about it they are due for their first check, I have over 25,000 miles on it.... I like screw type adjusters, and I really appreciated my Harley's hydraulic lifters. __________________ Happy to serve.
	0

02-25-2011, 09:02 PM	#13
recracer Join Date: Jul 2009 Location: Charles Town W.V. Posts: 849	this engine can not be brought into the usa at this time
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