how much should it cost to port a cylinder?

[ballzdeep38]

I am looking to do a top end on my R and I figure i might as well port the cylinder now since its already off the bike. I have a few questions about it.

1: how much should it cost to have the cylinder ported? I would like a wide powerband (well for a 2 stroke anyways). Something that will work for all around riding (trails, dunes and mx).

2: I am thinking about boring the cylinder too. i know i can go to a 269, but i was wondering how that would affect my eligibility in mx races? will i have to run the open class even though its a stock cylinder? how big can i go (if any) and still be eligible for a 250 class or a 250/450 class? i already have a pipe so its going to be a MOD class.

[fastR of puppets]

ive never heard of Rs not running in open lol

porting should go for about 200-300

i believe tho that in races for 250rs, generally your aloud a 265

but boring it out isnt gunna give you that much more power and its gunna take away your possibilty of boring it later if you need to because of engine damage

and you said the best powerband a 2 stroke could have, well 4 strokes have the powerband of a lawnmower if you were thinkin that they had a broad powerband

[Wacko Jacko]

u can talk to eviltwin about pricing , i hear they do real good work, and as far as type of porting, a dune port would be alot different than an MX port im sure, mx would be more focused on low end , but either way it will rip , i doubt you would want to run a dune ported cylinder on a mx track, but im sure a mx ported cylinder would still run awesome in the dunes, itll be way ahead of a stock port, so u cant go wrong

[fastR of puppets]

ya dont get a dune port, mx port gives you a nice alround powergain

[atcsteve]

Yea,talk to eviltwin! I hear he does great work,and you will be happy with a correctly ported cyl.!! Be careful and not let "just anyone" do the work.You can find many guys who say they can port,and then you end up with a jacked-up cyl!!!When they are done right,you'll get reliability,and performance! Good luck.

[all250r]

Originally Posted by ballzdeep38

I am looking to do a top end on my R and I figure i might as well port the cylinder now since its already off the bike. I have a few questions about it.

1: how much should it cost to have the cylinder ported? I would like a wide powerband (well for a 2 stroke anyways). Something that will work for all around riding (trails, dunes and mx).

2: I am thinking about boring the cylinder too. i know i can go to a 269, but i was wondering how that would affect my eligibility in mx races? will i have to run the open class even though its a stock cylinder? how big can i go (if any) and still be eligible for a 250 class or a 250/450 class? i already have a pipe so its going to be a MOD class.

Well if you want to ride in a 250/450cc class and have the torque range of a 4stroke then what's wrong with 450cc's? lol 2strokes don't have to have a narrow powerband if you're comparing apples to apples. These days it seems everyone overlooks that the 450 has 200 more cc's to compete in a 250cc class. Get a sabertooth if you want a massive torque spread and wipe your arse with "modern" quads. Otherwise, 250cc 2strokes can be customized to have a lot of fun! moderate port timing with a well matched pipe and intake dimensions will make a really nice motor!

[fiveOnick]

Just for safety leave the stock cylinder at 68-68.5 max, they have issues with breaking the skirt after that point. If you really want to seriously MX a 2stroke I would look at a PV. Peak hp and a smooth curve comparable to a built 450 is not obtainable on a 265cc limit. Not to say it is completely with a PV either but it will easily be more competitive.

[flotek]

my old ported 4mill stroker honda250R with ESR ignition made an awesome mx and trail setup for usable power and very good lowend torque considering the displacement .very broad power ,i would go that route if I wanted a killer MX setup and had the funds .granted it didnt have the off idle insane torque of a good running piped YFz450 ...but it sure would pull your arms off and wheely up at anything over 1/4 throttle and blow by most any 450 in 300 feet

[fiveOnick]

Yeah a 4mm is another option, but it easily crosses the 265cc limit at anything over 66.5mm. Not to mention it costs another 300 at least to just for the crank, bearings, and gaskets. Then head mods to accommodate. Granted its cheaper than a PV but not quite as effective for MX in my opinion. If class specs are essential your choices are limited. I think the PC2000 265 is the best choice on the market currently, ported by another builder than Duncan. That is expensive though.

Alky makes great useable power, but it also wears you out. Even though mine has big bore torque it come into the band on the TRX5 very hard and is a handful to ride. Plus I doubt alky is legal, not to mention an ignition change is a must.