Rt1 vs rt1m mx and rt2 3 vs rt2mx

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Chiefs online
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Rt1 vs rt1m mx and rt2 3 vs rt2mx

Post by Chiefs online » Thu Sep 13, 2018 11:08 am

I am sure this has been gone over before. Im curious the engine differences between these
enduro's and their mx brothers. I know they have a gyt kit that is head carburetor pipe and piston, but I am curious if the cylinder is different other than the lack of compression release. I have both stock rt1 cylinder and rt3 cylinders. With the stock rt1 cylinder would there be an improvement by using the rt1mx piston? (I heard it has a shorter skirt for longer intake opening) same question for rt3 cylinder with rt2mx piston. I am requiring a rebuild and see I can get both piston port and reed port mx pistons and wondering what I'd be getting into. Thanks for any info.
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Difference between rtmx and rt enduro cylinder jugs?

Post by Chiefs online » Sun Sep 16, 2018 9:58 am

Sorry if I got too winded with that question. I just ordered a stock rt3 piston. Also ordered an rt2mx head. Can anyone tell me what's different between rtmx and enduro cylinders? I'm mostly concerned with exhaust port placement. I don't have an rtmx cylinder to compare to. I used to have good luck with this site, but I'm starting to wonder what happened to everyone. I will post pics after someone shows interest..
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MarkT
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Post by MarkT » Sun Sep 16, 2018 11:26 am

Porting is different... searching the Internet can find diagrams with the "port maps" for many of the MX models... GYT cylinder cylinder could be even different than MX depending on year and model. Enduronut is one of the experts on this.

MX head has a smaller volume which raises compression. The MX model has a higher exhaust port so the smaller head volume restores lost compression due to the later exhaust port closing. Unfortunately, using the MX head on a stock cylinder will result in way too much compression.

For pistons, and piston questions, again, contact Enduronut. He has what might be the best supply in the world of pistons and rings including many of the hard to find ones.
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Compression distance

Post by Chiefs online » Sun Sep 16, 2018 6:40 pm

thanks for the info. Would anyone be willing to take a measurement between top of exhaust port and top of cylinder? I am curious how far off they are, if anyone has a rt mx cylinder sitting on the shelf.
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Rt2mx top end

Post by Chiefs online » Sun Oct 21, 2018 10:03 am

In case anyone else is thinking about trying something like this, I pieced together an rt2mx top end and it works quite well. I had a brand new stock rt3 piston, that's what I used in the mx jug, minus the second ring. The power band is way higher, comes on very hard when it gets there. The clutch slips horrible so I'm getting clutch springs for an rt2mx and new clutch plates. I'm also going to gear it down to get the motor into power band quicker. If you enjoy putting your enduro around I wouldn't recommend it. Otherwise power gains are very noticeable.
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