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500t head volume vs 450? anyone ever measure it?

1290 Views 9 Replies 6 Participants Last post by  Badbiscuit
some say the 500t head has more volume in the dome, i.e. less compression. I can see it is a different casting, and has not got the steel dome in it. does it also have a slightly bigger volume, that is to say it is lower compression?
I observe that the pistons have less dome than the 450; what about the head?

thanks, Brian
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The Honda 450 manual lists the compression ratio as 9.0:1.
The Honda 500T manual lists the compression ratio as 8.5:1

Though the 450 manual specifies 185 psi as the desired compression reading, the 500T manual makes no mention of a desired compression reading.

In that context, it would be reasonable to assume the 500T would deliver somewhat lower compression readings.
Since the bore on both bikes is the same, one could assume there is a difference either in the piston dome, or the head "squash" area itself, or maybe both.

That's about all the info I can offer, hope it helps......
450roo said:
I would be very interested to see a brakedown of the changes between the 450 and 500T. It seems strange that a 2mm lengthening of the stroke and a change in gearing can make two motors that behave so very differently. I suspected that the cams are different but thay don't seem to be on visual inspection. Allan
Same cams, different crank, different head, different carbs, differnt pistons, lower compression ratio, different tranny, different mufflers. Different seat, forks, shocks, lights, instruments.
Most everything else is the same, just cosmetic differences....
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