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Old 02-06-2015, 09:56 AM
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mapbike mapbike is offline
Motorized Bicycle Elite Member
Join Date: Mar 2010
Location: Central Texas
Posts: 5,379
Smile Re: Curious about the engine, :question:

Originally Posted by cannonball2 View Post
When this DragonFire engine came out I began to look for a intergrated CDI that would work with the CG rotor. The rotor is very small and the units I thought of from weedeaters were radiused for a larger flywheel. Havent given up yet. We all know that even the Chinese throw away trimmers have no/little ignition issues and are often left out in the rain on trailers of landscapers. This is the way to go.

After all this discussion it seems the only way to get a piston to the top 38mm engine is to use the crank with the 114mm FM80 rod and its matching piston. These are I believe Grubee parts. I think my engine in a box is basically a GT5. The stuff looks like Grubee quality. The GT5A/Super Rat? has a different jug, its the one to find. I believe it will have a 50mm exhaust stud spread? If that is the case then it must be design ported for that crank/piston combo since the jug would be a recast anyway. Seems the ignition was the main issue with this engine.
I have nothing against the super rat engines personally since I have never owned one, but I truly see nothing to gain by having one over the much better balanced engines we have access to nowadays like the dax engines and even the "Half Breed" engines that seem to have better balanced cranks than some of the older designs.

I'll just stick with what I have the largest selection of parts and pieces for, no reason to make things more complicated than need be for me....LOL!

since 2009 I've yet to have a single ignition failure and nearly every conversation I have ever seen on here concerning the S.Rat the junk ignition comes upand all the trouble people have had with them, I've also seen where it has been said that the heads like the Manic Mechanic "Ashtray" head wont work on the GT5A/S.Rat engines, I assumed that this is because they actually either have 6mm studs like I remember reading somewhere once, or the bolt pattern is different.

The "Dragonfly" engines may be a whole new breed with things being even different than the S.Rat was/is, seem Bikeberry say the Dragonfly has 8mm head studs, and says nothing abouit having the 50mm exhaust stud pattern.

I'm just not to keen on the ignition since there is such a bad track record with then on the S.Rat engines.

If you get one of those engines keep us posted on how it turns out and what the overall balance is like.

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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