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How did you Unleash the Beast in your RMZ 250? Best engine mod combo's for the buck??

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Question for those of you that have done some power mods to your '07, '08, '09 RMZ 250:

How did you Unleash the Beast in your RMZ 250? Everyone knows the RMZ has a great low-to mid powerband, but lacks somewhat on top, right? What were your best engine mod combo's for the buck?? One prerequisite: must run pump gas! The other prerequisite is to spend as little $$ as possible.

For instance, it may have been a PC Ti4r complete exhaust and a JP hi-comp piston that worked the best for one of you. Someone else may have spread the power with an FMF or Yoshi slip-on, a Loudmouth Air Filter and a Boysen X-wing. Another may have just done a hi-comp piston or something.

I've got an '08 RMZ 250 that I use for 50/50 moto & off road. Suspension and ergos are all done, but motor is stock. I'd like to broaded the powerband without giving up reliability or low-end power. I absolutely love the low-mid powerband and do not want to sacrifice that.

Thanks guys, I'd really love to hear what you've tried, what worked and what didn't work. Give all the details, like what piston and compression ratio you found provides benefit without requiring race fuel, etc?

FishFreq

------<')))><

"I'm sort of a rekluse..."

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For me and my 08 ...FMF 4.1 slip-on and 13/50 gearing was best upgrade under $500. I have alot more performance upgrades, but again, for under $500 this was the best combo and worth every dime.

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I said it before..but head porting is best bang for buck.

it gains everwhere, and doesn't loose anywhere.

on the rmz that and a pipe are all you need to have a solid motor.

It already has 13.5:1 stock compression, any more than that without cams usually shows no improvement in hp.

Ron Hamp has a custom JE he made that has shown hp improvements...but it's marginal on pump fuel (id advise agianst running pump on it)

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Im am too looking into putting some more power into my 09 rmz.

I also love the bottom end power and dont wish to lose any, mainly used for mx. Im thinking of getting a yoshi rs2 slip on and changing to 13/50 gearing.

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The only sure fire way to unleash the beast would be to trade that RM in for a CRF 250.........................

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im also interested in this. i Have a 08 RMZ250 with 15 hrs. I am going to change the stock 12/48 gearing to 13/50 which i have heard is good? I am also getting a ti-4 pipe.

How much is head porting and what is it? What gains would we be looking at?

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I said it before..but head porting is best bang for buck.

it gains everwhere, and doesn't loose anywhere.

on the rmz that and a pipe are all you need to have a solid motor.

It already has 13.5:1 stock compression, any more than that without cams usually shows no improvement in hp.

Ron Hamp has a custom JE he made that has shown hp improvements...but it's marginal on pump fuel (id advise agianst running pump on it)

Good post.

I had head work done to my '07 and now the bike rips. The tuner advised me to get the best out of it to use a High comp piston and get a slip on exhaust, so for this year I installed a CP piston and an FMF power core and the bike is better still. I'm very pleased with it and best of all have had two years of mods and still spent less than the Ti PC full system I had planned on getting.

I've never seen the benefits of a high comp piston in a standard engine.

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Quote....

The only sure fire way to unleash the beast would be to trade that RM in for a CRF 250.........................

trade in a RMZ for bog monster???? been there... wont look back until efi is dialed in. that bike has been over rated since 06

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I never did mention the year so lets make it an 06 CRF 250 that should solve all your RM problems hahahahahahahahahahaha!!!!!!

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I never did mention the year so lets make it an 06 CRF 250 that should solve all your RM problems hahahahahahahahahahaha!!!!!!

You must be over here because your considering buying an RMZ??... come on you can tell us, we'll welcome you in friend...I know its embarassing having to bump start your crf thru the pits while the rmz guys are hammering out laps??

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yaa its true i always wanted an RM my affection for the brand comes out in teasing sorry guys !!!! but seriously the only other bike i would even think about buying(other than 08 CRF450R) would be the 09 RM 450 i think suzuki has it made in the shade when it comes to the new EFI!!!!!! but nothin beats HONDA ...........................HONDA for ever!!!!!!!

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yaa its true i always wanted an RM my affection for the brand comes out in teasing sorry guys !!!! but seriously the only other bike i would even think about buying(other than 08 CRF450R) would be the 09 RM 450 i think suzuki has it made in the shade when it comes to the new EFI!!!!!! but nothin beats HONDA ...........................HONDA for ever!!!!!!!

Alright 'J-no-class', go back to your forum! ...and we'll stay away from your 'fix my CRF 250 bog', 'make my '09 CRF 450 handle normal', 'my crank oil keeps running low' and 'how do we fix this efi and make it not flame out' threads.

LOL! You forgot to mention, "...nothing beats (up) HONDA except for Honda owners :) !" Don't throw stones when you live in a glass house....

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sounds like you have done your fair share of Honda forum touring yourself! with all that fix it please knowledge!!!dont worry mate Ill stay out of the RM forum Ive got bigger FISH to fry anyway. LOL .............................................oh and here is a delightfull side note Suzuki released a bike last year that had a case that imploded upon startup! nothin like a recall to add respect to your brand name... we all have are problems but here is the great part we all share insane love for the two wheel motion!!!!!

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sounds like you have done your fair share of Honda forum touring yourself! with all that fix it please knowledge!!!dont worry mate Ill stay out of the RM forum Ive got bigger FISH to fry anyway. LOL .............................................oh and here is a delightfull side note Suzuki released a bike last year that had a case that imploded upon startup! nothin like a recall to add respect to your brand name... we all have are problems but here is the great part we all share insane love for the two wheel motion!!!!!

2009 honda crf450rs had a recall to buddy. Most revolutionary bike my ass.:)

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sounds like you have done your fair share of Honda forum touring yourself! with all that fix it please knowledge!!!dont worry mate Ill stay out of the RM forum Ive got bigger FISH to fry anyway. LOL .............................................oh and here is a delightfull side note Suzuki released a bike last year that had a case that imploded upon startup! nothin like a recall to add respect to your brand name... we all have are problems but here is the great part we all share insane love for the two wheel motion!!!!!

guess honda didn't have a problem with the decompression pin.

Or the transmissions.

Or the bike in general......

You know what!? I just realized everyone should buy honda seeing how it is my main stapple of business, between the constant valve replacements, occastional idiot who runs the bike out of engine oil because he didn't think the crank seal could go (is this his fault), and the typical carb work that they require, I hav to admit. I love honda's.

Go buy another!

Anyways....You obviously know more than us regarding RMZ performance.

For the guy who asked...

Porting is the process in which the tracts that feed air into and out of the cylinder are reshaped to improve cylinder fill.

It MUST be done by someone who knows their stuff, but don't always think PC or MDK are the best bet.

Ron Hamp

Jesse Williams

and a huge host of other people can get you major improvement.

In the suzuki's case, many top tuners actually fill in the port in conjuction with reshaping to not only improve flow, but to increase velocity. Good porting by itselft can be worth 2.5-3 hp in the zook's case and can be had for about 400 dollars typically including valve seat work (to improve flow as well)

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Porting is the process in which the tracts that feed air into and out of the cylinder are reshaped to improve cylinder fill.

It MUST be done by someone who knows their stuff, but don't always think PC or MDK are the best bet.

Ron Hamp

Jesse Williams

and a huge host of other people can get you major improvement.

In the suzuki's case, many top tuners actually fill in the port in conjuction with reshaping to not only improve flow, but to increase velocity. Good porting by itselft can be worth 2.5-3 hp in the zook's case and can be had for about 400 dollars typically including valve seat work (to improve flow as well)

Good info Harrperf, and shopping for a skilled port doctor is akin to searching for a brain surgeon; pick a bad one and you could end up brain-dead. Some use 'flow bench' metering equipment that can measure if their porting mods are actually improving cfm's or velocity, and some appear to do fine without it. It would be fun to hear about some of your experiences either way, and what tuning company you went with. More specifically, how the porting benefitted the placement of your powerband.

Oh, and hopefully that loose cannon 'Jclass' guy found his way back to his forum so we can get back to what we came here for, to exchange RMZ info!

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sounds like you have done your fair share of Honda forum touring yourself! with all that fix it please knowledge!!!dont worry mate Ill stay out of the RM forum Ive got bigger FISH to fry anyway. LOL .............................................oh and here is a delightfull side note Suzuki released a bike last year that had a case that imploded upon startup! nothin like a recall to add respect to your brand name... we all have are problems but here is the great part we all share insane love for the two wheel motion!!!!!

Sage advice is, "keep your friends close, and your enemies closer", so knowing the competition is just as important as knowing your own bike. The important part is both our manufacturers are owning up to those major problems and fixing them. We're gonna see a few stumbles with this next step up to EFI too and you can see that some co's like Yamaha are just standing back and waiting for the dust to clear. Smart decision? We'll look back in a few years and see all so clearly...so ride on and attack with the sun at your back!!!

Yes, the same blood runs thru our veins Jclass!

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like someone said, i think the quick/easy way would be a pipe and gearing but of course the headwork is also an awesome option. the great thing about the rmz is that with only a small amount of work, the engine is awesome and the handling is already best in class IMO

jclass, why are you posting here?

/yourself

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