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eric gorr rm125 big bore 155cc?

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has anyone actually had a rm155 / rm150 stroked and bored, if so how was it ?

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My friend and I both sent our topends to Eric last winter -- I got a big bore RM144 kit and he got the YZ144 kit. Our bikes both ran awesome (and very similar) after this.

He liked riding his so much that he sent it back to get the YZ153 stroker done. He had some troubles jetting it in but has it running good now. The biggest thing I noticed in comparison is it has a lot more lowend now so you can ride it alot easier without abusing the clutch.

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Jetting the RM was easy, really close stock. I just moved the clip and fiddled with the air screw.

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+1 on the EG RM144

I have one and the thing is fun, fun, fun...pretty reliable so far...

Def worth the cash...

Jetting.. NorthEast Fl

Pilot-40 but wideband shows its lean...42.5 is stock

Main- 370

Needle-stock...2nd clip

Airscrew...1 turn out

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I wanted a reliable bike so I went with the pump gas option with all around power. Some people say you can move the power around with the expansion chamber vs. the head/porting but I am no expert on that at all:banghead:

I have read that the RM is a mid-top bike and that seems to be the case so I def think it got some more low-end but that could be just the increase in power. I think the YZ has more low end to begin with so it might lug even better after the kit.

I was very close to going for the low end cause I was coming off a 4t but I opted for all around power b/c of what I mentioned above. I doubt I would be able to tell a difference but I may send it back to him for the change once I get used to the new power. Only have about 9 hours on the engine and I am fairly new to riding a 2 stroke again. Every's new for me right now.

I rode a 2012 KTM 150sx last at the KTM Demo ride and that bike def has more low end than my bike. It's noticeably stronger IMO but I think my bike pulls just as hard in other areas. They were very similar though the KTM has a tad more power IMO. Just saying that I am very happy with the RM:ride:

I am also running the FMF Fatty and it seems to move the power closer to mid rather than top. Again, I'm going by feel with very little time on the bike and I am no expert at all. It's never been dyno'd so I could be totally wrong but I seem to like the Fatty pipe over the stock pipe. It seems more managable to me. VET C rider working on moving up to B...95% MX 5% Trails...

Be patient when calling him...he can be tough to get a hold of...For some reason...8:45am seems to always work for me...He's a nice guy with great prices.:lol:

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Thanks thats a great read and very helpful, I had a 2006 Athena yz144 and loved it, this RM was my son's but he is giving up racing now so I thought I would give the RM a go. I was racing a yz250 this season, it was great on practice days but when in race mode it killed me. you have to be fit to ride one at race pace. I'm 42 now and not as fit as I would like to be but just want to have some fun.

I think I will go for the mid to top and hope there is some bottom end.

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