Eric1897

Hotrods + high compression piston

31 posts in this topic

Posted (edited)

Hey so I just want to know if anyboy had experience with a +2.5mm hot rod crank is it a big difference from OEM and does it require race fuel and what about performance also has anyone mixed it with a high compression piston (13.5-1)if so how is it like look to do a rebuild soon (no troll) thanks guys :ride:

Edited by Eric1897

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It’ll more than likely raise the compression to where you will need to run race gas to prevent detonation.

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With that kind of build would you recommend anything else to and for support?

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Just now, Eric1897 said:

With that kind of build would you recommend anything else to and for support?

My own personal opinion is to stay away from the stroker cranks. Stick with a stock one. 

They put more stress on all engine parts and can lead to premature failures from what I’ve seen.

If you are going for an all out A-class race bike, go for it, but the HP gain isn’t needed if you aren’t going to use it. You’d be better off buying Stage 2 cams and having the bike remapped for the cams and pipe, but you’d more than likely still need race gas.

The higher the compression, the higher octane you need unless you retard the timing, which would bring you back to where you started and the bike would ride different. 

I would keep it within stock specs with a HC piston and remap it for that. You should be able to get away with 93 pump with that, but any more compression than that and you may be straying into race gas territory. 

I’m not sure what pipe you have, but any aftermarket pipe would lose some weight and add some HP vs. stock, especially if it’s remapped for it. I definitely noticed a difference on my bike with a Yoshimura system and it had more bark that I loved in corners and single track. 

No sense in making a race motor if you don’t ride the stock one to it’s full potential. It’ll only decrease the life of the engine and more money out of your pocket in wear items.

Just my 2¢, not saying you absolutely shouldn’t do it.

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On 5/12/2018 at 2:56 PM, hondaman331 said:

I was sort of like, yeah ok, different strokes for different folks....but then I saw said banshee picture and was like this is the dumbest waste of money ever

 

1 minute ago, MaybeMe said:

My own personal opinion is to stay away from the stroker cranks. Stick with a stock one. 

They put more stress on all engine parts and can lead to premature failures from what I’ve seen.

If you are going for an all out A-class race bike, go for it, but the HP gain isn’t needed if you aren’t going to use it. You’d be better off buying Stage 2 cams and having the bike remapped for the cams and pipe, but you’d more than likely still need race gas.

The higher the compression, the higher octane you need unless you retard the timing, which would bring you back to where you started and the bike would ride different. 

I would keep it within stock specs with a HC piston and remap it for that. You should be able to get away with 93 pump with that, but any more compression than that and you may be straying into race gas territory. 

I’m not sure what pipe you have, but any aftermarket pipe would lose some weight and add some HP vs. stock, especially if it’s remapped for it. I definitely noticed a difference on my bike with a Yoshimura system and it had more bark that I loved in corners and single track. 

No sense in making a race motor if you don’t ride the stock one to it’s full potential. It’ll only decrease the life of the engine and more money out of your pocket in wear items.

Just my 2¢, not saying you absolutely shouldn’t do it.

Thanks so much for for your input just to give alil Redd back my rmz450 has full fmf 4.1 t.i pipe rct with mega and that added a good boost hands down and I was looking to add stage 2 cams as well see the type of riding I like doing is like open field/desert all out riding that's why I want to add alil more hp and I wouldn't might just using race fas because I tend to only really ride weekends typically but I tend to want to turn my bike on to a hard hitting arm breaking machine lol.. 

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4 minutes ago, Eric1897 said:

 

Thanks so much for for your input just to give alil Redd back my rmz450 has full fmf 4.1 t.i pipe rct with mega and that added a good boost hands down and I was looking to add stage 2 cams as well see the type of riding I like doing is like open field/desert all out riding that's why I want to add alil more hp and I wouldn't might just using race fas because I tend to only really ride weekends typically but I tend to want to turn my bike on to a hard hitting arm breaking machine lol.. 

I would look towards having the bike remapped. I believe Tokyo Mods sells an ECU for the bike if you want to go that route.

Are you using the lean map coupler? Also did you cut the screen out of the air filter cage?

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Just now, MaybeMe said:

I would look towards having the bike remapped. I believe Tokyo Mods sells an ECU for the bike if you want to go that route.

Are you using the lean map coupler? Also did you cut the screen out of the air filter cage?

Well the real only mod I have on bike Is just the fmf and air filter screen isn't taking out...does that make a diffs??

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20 minutes ago, Eric1897 said:

Well the real only mod I have on bike Is just the fmf and air filter screen isn't taking out...does that make a diffs??

It does add a little snap to the bike and lets it breath. You can also buy an RM filter cage I’m pretty sure and it doesn’t have the screen. I’d double check to make sure they are the same shape and size first.

Do you have the lean coupler?

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Just now, MaybeMe said:

It does add a little snap to the bike and lets it breath. You can also buy an RM filter cage I’m pretty sure and it doesn’t have the screen. I’d double check to make sure they are the same shape and size first.

Do you have the lean coupler?

No everything is pretty much stock no ecu nor couplers now I have been looking at reviews of the vortex ecu have you had any experience?

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1 hour ago, Eric1897 said:

No everything is pretty much stock no ecu nor couplers now I have been looking at reviews of the vortex ecu have you had any experience?

I haven’t, just a recommendation if you are running race gas and a pipe and want to get as much power as possible. 

Did you buy the bike new? The bike should have came with white and grey couplers that plug in under the number plate. Grey is rich, and white is lean. I think stock is green? The lean coupler wakes the whole bike up and makes the engine have a little more “oomph”.

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7 minutes ago, MaybeMe said:

I haven’t, just a recommendation if you are running race gas and a pipe and want to get as much power as possible. 

Did you buy the bike new? The bike should have came with white and grey couplers that plug in under the number plate. Grey is rich, and white is lean. I think stock is green? The lean coupler wakes the whole bike up and makes the engine have a little more “oomph”.

So bike was brought of craigslist used but mint condition/showroom condition now I'm not so familiar on couplers so I have some pics now I did check the air filter and is this the screen you are referring to??

20180517_185542.jpg

20180517_201236.jpg

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Posted (edited)

Yes that’s the screen. As long as your bike doesn’t backfire often, you can cut it out. It allows it to breathe better.

And that black connector is the map coupler. You can buy a lean one, which is white.

Part number is:

36852-28H00

Fits from 2010 to 2018.

edit: if you ride woods or ohv trails, I don’t recommend cutting it as it could potentially catch fire. You should use a fire-resistant oil and filter. I believe Twin Air makes some.

edit2: The filter part number is 153216FRX. Pre-oiled filter kit.

Edited by MaybeMe

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7 minutes ago, MaybeMe said:

Yes that’s the screen. As long as your bike doesn’t backfire often, you can cut it out. It allows it to breathe better.

And that black connector is the map coupler. You can buy a lean one, which is white.

Part number is:

 

36852-28H00

Fits from 2010 to 2018.

If you dont mind me askin what is the difference from the lean coupler also I was looking to going to a loud mouth air filter soon

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8 hours ago, Eric1897 said:

If you dont mind me askin what is the difference from the lean coupler also I was looking to going to a loud mouth air filter soon

It leans out the entire fuel map. Will give it more grunt. They come with the bike when you buy them new. I always ran the lean coupler on my bike and it was very grunty and picked up the front wheel like nothing.

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On 5/18/2018 at 5:34 AM, MaybeMe said:

It leans out the entire fuel map. Will give it more grunt. They come with the bike when you buy them new. I always ran the lean coupler on my bike and it was very grunty and picked up the front wheel like nothing.

So I found a JE high compression piston that is 14:5.1 ratio is higher the compression mean high hp/performance??

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9 hours ago, Eric1897 said:

So I found a JE high compression piston that is 14:5.1 ratio is higher the compression mean high hp/performance??

Yes, exactly.

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So I found a JE high compression piston that is 14:5.1 ratio is higher the compression mean high hp/performance??

Be careful how high you go unless you plan on running strictly race fuel. You will be right on the bubble of your motor forcing you to run race gas.

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5 minutes ago, BDubb106 said:


Be careful how high you go unless you plan on running strictly race fuel. You will be right on the bubble of your motor forcing you to run race gas.

Yea I was going to just put race fuel in there because I tend to only ride weekends and I would buy a 5gal which should last quite a bit have you had any experience with high cp pistons?

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16 minutes ago, Eric1897 said:

Yea I was going to just put race fuel in there because I tend to only ride weekends and I would buy a 5gal which should last quite a bit have you had any experience with high cp pistons?

Yeah... my RMZ had a full mod motor. CP 13.5-1, full mod head, webcamshaft race profile cams, injectioneering throttle body mod, blue print bottom end with balanced crank and CP rod and ISF, full Yosh, mapped ECU. The high compression piston may add 1-2 HP (depends on bike and other mods to compliment the piston) but you will get better gains from other parts. It will feel like you gained power but really all you are feeling is the engine reving faster. You would be better off with a stock compression piston and a cam or minor head mods to gain the added power you are looking for. You can get massive power out of some pretty simple head mods and a proper remap. Best part is that you can gain the power you are hoping to gain and still have the ability to run pump gas if you wish. 

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1 hour ago, BDubb106 said:

Yeah... my RMZ had a full mod motor. CP 13.5-1, full mod head, webcamshaft race profile cams, injectioneering throttle body mod, blue print bottom end with balanced crank and CP rod and ISF, full Yosh, mapped ECU. The high compression piston may add 1-2 HP (depends on bike and other mods to compliment the piston) but you will get better gains from other parts. It will feel like you gained power but really all you are feeling is the engine reving faster. You would be better off with a stock compression piston and a cam or minor head mods to gain the added power you are looking for. You can get massive power out of some pretty simple head mods and a proper remap. Best part is that you can gain the power you are hoping to gain and still have the ability to run pump gas if you wish. 

Idk if u read back in the post but I was looking to do a hot cam stage 2 with the high cp piston also with the hot rod 2.5mm crank and also was going to add the vortex ecu map also I have a full fmf 4.1 system

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