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my hotrods 4 mill 115 long rod crank just came in so im currently in the prosses of putting that in, just waiting on some seals and stuff, but i have a friend thats talking alot of shit and thinks his stock piped and jetted crf450r is the most powerful bike there ever was. and everybody in town is sick of it. so i need to be able to walk all over him on pump gas. im gonna get some v force 4s, adjustable timing plate and a cool head, and i already have T5s.

 

how do you guys think i will do with this set up? let me know if theres anything else i should do or change

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Is your port job matched to the 4 mil crank?

Last time we were at little sahara I raced my friends crf 450 against my then pretty stock banshee. I could take him from a rolling start and he would catch up and barely pass at higher speeds.

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Putting it in simple terms, if you don't have it ported for the 4 mil, the pistons will be going down 2 mm below the ports and that 2mm of stroke will be doing very little for you. There's more to it than that, but that should give you a basic understanding of how dumb it is to not get it ported for the 4 mil.

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yeah but i thought that they made pistions for the 4 mill to make up for that? im not gonna try and be complicated if i need to get it reported thats what im going to do. and where would you guys recommend to buy a cool head and domes from ? and what size domes for pump gas?

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The Wiseco 795 pistons are to make things right with the 5mm longer rod. That has nothing to do with the 4mm longer stroke and the port timings. The piston will travel 2mm out the top of the cylinders and 2mm below the ports. You really need to talk to a builder to get your porting taken care of and get your domes.

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