Thread: 40 MPH Club
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Old 02-22-2015, 03:56 AM
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Join Date: Mar 2010
Location: Central Texas
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Default Re: 40 MPH Club

Originally Posted by Davezilla View Post
Yup.. the better balanced they are the higher they can rev not to mention the more comfortable the ride will be with no vibes at the seat or bars.
Ill tell ya Dave, Im so impressed with the balance of this old used GT5 lower I bought from YesImLDS, what has me scratching my head a little is the fact that befors I went together with it I could actually see a tad bit of wobble in the crank counterweights but I decided to just stick a jug on it and see what it would do.

Is it butter smooth? No not quite, but its comfortably smooth and really winds up considering the NT carb and the slightly modified stock pipe.

It's a tad weak in the upper low to mid low rpms for some reason bit it has good low speed lugging power and revs fairly quick and purs like a kitten at its max rpm which I actually have no idea what that is currently.

I had a different personality than my 40mm stroke dax engines, but Im not100% sure why yet, hard for me to believe its due to the 38mm stroke but it could be the 38mm stroke and long rod combo along with what that zeems to do to the port timing.

Im thinking about pulling the jug, adding another base gasket, shaving the deck some to compensate for the lossof height at TDC and see what that does to it.

The issue Im seeing with it right now is that although it duns reLly good and has good power rdown low, its lacking in the medium to upper rpm a little, it hits 40mph quickly on the flat and then sorta peters out like its governed at that certain rpm and the hills seem to affect it more than they do my 40mm stroke engines also.

As good as it runs with a 41T, I dont think it will pull a 36T well at all like it is now and my 40mm steoke dax engines pull a 34T and 36T as good or better on the hills than this GT5 does with the larger 41T.

Im gonna play with this engine a little now that I know it has a good enough balance to rev high without shaking a bike apart, I know Fred and others here have figured out how to get the best performan e from the GT5 geometry engine, but no one shares their " secrets " so Im gonna play with the one I have and see if I can find a sweet spot that Im satisfied with and then I will share the xetails of what I've done so maybe others can tweak their GT5 for better performance if Im able to make some improvements that is.

I want to do as much as I can and tey to keep it as simple as possible at the same time.

My goal is to get at lest 45mph on the flat out of this GT5 and Id like to get it by being able to pull at least a 38T sprocket.
I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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