Author Topic: New Honda GX630  (Read 7842 times)

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Offline Gui961

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New Honda GX630
« on: October 23, 2012, 08:59:46 pm »
The 3rd gen Honda vtwin Gx630-GX660-GX690 have been out for 2-3 years now, did someone try to run them or do some R&D.

Basic info it is a 90 degree vtwin, 42cid, hemi style combusion chamber, steel rod with bearing, forged crank shaft, Digital CDI ignition

I have done some research, it has some big problem with them.

-the head and cylinder is one piece, no head gasket, installing bigger valve may be impossible or bore them for more cubic inch

-the cam gear is plastic, so some kind of billet gear might be necessery, the cam do not use conventional lifter, its a rocker and the cam only have 2 lobe

-The Ignition is digital CDI, but they says it has a rev limiter build in, so if its like the others new engine its around 4000rpm, so others coil or electronic ignition need to be use

-Of course no billet flywheel for that engine , maybe one from another engine could fit...

More info would be nice, i have this in my head since i worked on a new generator using this engine this morning
Guillaume Mercier-Roy

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Offline saltyAMF

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Re: New Honda GX630
« Reply #1 on: October 23, 2012, 09:21:22 pm »
sounds like a performance disaster  too bad too
joshua "MEAT" coleman

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Offline Nod

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Re: New Honda GX630
« Reply #2 on: October 24, 2012, 03:34:41 am »

 Hi,

This problem from tuning the New Generation 630, 660 and 690 from Honda is not new to us either over here. :bash:

There are afew teams that have tuned the GX690 and one great problem is that the heads are incorporated with the bore :mad:
Therefore bigger Valves is virtually impossible. I my self have not realy looked indepth into the new engines, but what I do know is the main issue to tuning this type of engine is done with Digital Ignition and new programing of it!!

I'll do a bit of research in the winter months and post the results  ;)

MM-Nod
 

Offline Nod

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Re: New Honda GX630
« Reply #3 on: October 24, 2012, 05:13:23 am »
 By the way the 2nd Generation has also a cam with two lobes and a plastic cam wheel, togeather with the decompression bits :D
Sometimes it comes in handy that they are made out of plastic because when something gives then the cam and not the block :lol: