anybody tried this port job?

100hp honda · Post by **100hp honda** » April 22nd, 2008, 5:48 pm

ok, cut the bottom of the cylinder .040, raise the exhaust back up .040 to where it originally was, cut some unknown amount off the head, install FMF pipe then try to hold on

. anybody running this type of set up???

http://cr500riders.com/cgi/yabb/YaBB.pl?num=1208715963

dannygraves · Post by **dannygraves** » April 22nd, 2008, 5:56 pm

so... (-.040)+.040= try to hang on??? sounds more like "0" to me!

too bad Glen at GSS and DeWayne don't know about this...;-) their advise helped me not be able to hang on!

lewisclan · Post by **lewisclan** » April 22nd, 2008, 6:02 pm

NOT YET

100hp honda · Post by **100hp honda** » April 22nd, 2008, 6:12 pm

im not even going to try and understand that guys thinking.....but whats even funnier to me is the dude posting right before him "upgraded" to a DG pipe

. nothing against you fellers running DG pipes

lewisclan · Post by **lewisclan** » April 22nd, 2008, 6:34 pm

Ill leave the port majic to the experts . since I have 2 motors ported by guys that have built motors for world class titals. my Loomis motor on N02 has yet to have been beet ,

M.F.D.B. · Post by **M.F.D.B.** » April 22nd, 2008, 6:53 pm

Dude that guy is so smart he should try to teach Glen something...

ou812 · Post by **ou812** » April 22nd, 2008, 9:19 pm

Ya but 75% of the wannabies there will read that and go to town with that as dam good info and then pass it on as good info to others. Notice no one call out bullshit

lewisclan · Post by **lewisclan** » April 22nd, 2008, 9:32 pm

ou812 wrote:Ya but 75% of the wannabies there will read that and go to town with that as dam good info and then pass it on as good info to others. Notice no one call out bullshit

I dont think you can spell BULLSHIT on the other site

M.F.D.B. · Post by **M.F.D.B.** » April 22nd, 2008, 9:37 pm

Since my first attempt didnt work I made a second one...

Post by **MojoScojo** » April 22nd, 2008, 10:09 pm

100hp honda wrote:ok, cut the bottom of the cylinder .040, raise the exhaust back up .040 to where it originally was, cut some unknown amount off the head, install FMF pipe then try to hold on . anybody running this type of set up???

http://cr500riders.com/cgi/yabb/YaBB.pl?num=1208715963

Um, yeah. In two places. Eric Gorr's mo betta does this. I'm not sure of the numbers but it is effectively lowering the intake ports. It gives a lot more bottom end on both my 500 and my son's YZ 80. Much smoother power delivery. Probably lost some on top, but WAY more tractable.

"Try to hold on" hmmm. I dunno about that. Quite the opposite in my experience.

100hp honda · Post by **100hp honda** » April 22nd, 2008, 10:31 pm

im not familiar with gorrs work but i thought i heard he went up +1mm on the exhaust. so your saying he lowers the exhaust?? does he cut the bottom of the cylinder so it lowers exhaust, transfers and intake, or lower it with a port tool? i dont recall reading anything of cutting a cylinder in gordon jennings book

lets get a expert opinion on this- someone call pete loomis tomorow

Post by **MojoScojo** » April 22nd, 2008, 10:42 pm

100hp honda wrote:im not familiar with gorrs work but i thought i heard he went up +1mm on the exhaust. so your saying he lowers the exhaust?? does he cut the bottom of the cylinder so it lowers exhaust, transfers and intake, or lower it with a port tool? i dont recall reading anything of cutting a cylinder in gordon jennings book lets get a expert opinion on this- someone call pete loomis tomorow

No, Im saying he is lowering the intake. He shaves the bottom of the cylinder effectively lowering everything, then hogs out the top of the exhaust port to put it back where it belongs. And finally cuts the head to restore compression to normal levels. At least that is what was done to both of mine.

Sure turned my boy's YZ80 into one heck of a woods bike.

M.F.D.B. · Post by **M.F.D.B.** » April 22nd, 2008, 10:48 pm

All I did was skim my head .050 and put a Gnarly pipe and PWK on. My bike has bottom end like an XR650. I cant imagine needing any more bottom end!!

ou812 · Post by **ou812** » April 22nd, 2008, 11:34 pm

Mojo, your missing the point, everyone knows what that mod does, it's a way to retune a motor to 4 stroke power, which BTW Gorr evens says that. The point is the clown is passing the info off as some kind of monster arm rippin power. Being you have the mod done on the YZ you know he is full of shit.

dannygraves · Post by **dannygraves** » April 23rd, 2008, 7:47 am

Eric gorr in his book only talks about detuning the 500s and mellowing out the hit and shifting the power up. Nothing he has written about working on 500s would have resulted in difficulty hanging on, but maybe better times in an MX application since there would be less struggle to hang on!

blownbillybob · Post by **blownbillybob** » April 23rd, 2008, 9:53 am

ou812 wrote:Mojo, your missing the point, everyone knows what that mod does, it's a way to retune a motor to 4 stroke power, which BTW Gorr evens says that. The point is the clown is passing the info off as some kind of monster arm rippin power. Being you have the mod done on the YZ you know he is full of shit.

whos the real clowns now????? you guys are talking shit about something you dont even know about!!!! thats why you have to send your shit out to get worked on. alot of you guys are BENCH EXPERTS and never done SHIT!!! im really going to listen to (100HP HONDA) next time LOL!!! can you even explain why to cut .040 off the bottom and raise the exh. port.040 and just so you know 1mm=.0394 but you knew that RIGHT!!!!!!! and the ( try to hang on) was only a expression

ou812 · Post by **ou812** » April 23rd, 2008, 10:30 am

whos the real clowns now

Well lets have a look. Being your not a " Bench Expert" we will asume you are a real "Expert" unless you want to post something to a differant effect.

So as you are the expert your mod drops the barrel 40 then you say raise the exhaust 40, so the effect is you dropped the transfers 40.

That is know to most as a detuning method, maybe in the world of real experts like yourself it is something else, but again you don't say what.

( try to hang on) was only a expression

So now in your defence you are now saying your expression should not be taken as desciption of your mod?

whos the real clown now?????

see the above, BTW.......... :bsmeter:

Post by **AlisoBob** » April 23rd, 2008, 10:33 am

The port timing mods described are prolly' within Hondas own production tolerances...

Post by **AlisoBob** » April 23rd, 2008, 10:41 am

blownbillybob wrote:...you guys are BENCH EXPERTS and never done SHIT!!!

Yea, your right....

We just build A/F's equal or better than S/H, put nitrous kits on bikes, build and ride hilclimbers at National levels, send our parts to one of the best machinists around ( GSS ), stick with OEM and not follow the " Trick of the Week" junk......, have several "SITE" rides per year in all disciplines ( Sand, Hills, Singletrack, Forrest, Dez, Family Day, etc..etc..)

We also machine our own A/F billet hardware, clutch, and ignition covers.

Were goobers allright. You nailed it.

MICK · Post by **MICK** » April 23rd, 2008, 10:41 am

I've always believed in mods that complement one another. Like it wouldn't make much sense to put a torquey set of cams on a 2.0 liter rice rocket would it? The small motor needs some serious rpm to make lots of power ...so a cam profile favoring high rpm should work better right?

What I don't understand Billybob is why mellow the hit out, then go and put a pipey FMF on...to produce a motor with less bottom AND top end

I've ridden 500s like that before...they needed rebuilt.

But like they say, one man's garbage is another man's treasure. I often don't understand why some of you do the things you do. Like the poll on carbon fiber parts. I think the overwhelming vote was for carbon fork guards . Why in the hell anybody would want those is beyond me?? Like a thick decal wouldn't do the same! Or a billet gas cap...or machined axle blocks...alloy exhaust flange. To each his own

Shit I think the stock motor is fast enough as is.

Post by **AlisoBob** » April 23rd, 2008, 10:45 am

Carbon is one of the WORST materials to make bike parts from.

Kevlar is WAY better, but not as sexy.

I remember seeing that thread.... talk about being a "bench racer"..

Good one Mick...

dannygraves · Post by **dannygraves** » April 23rd, 2008, 11:12 am

blownbillybob wrote:
ou812 wrote:Mojo, your missing the point, everyone knows what that mod does, it's a way to retune a motor to 4 stroke power, which BTW Gorr evens says that. The point is the clown is passing the info off as some kind of monster arm rippin power. Being you have the mod done on the YZ you know he is full of shit.

whos the real clowns now????? you guys are talking shit about something you dont even know about!!!! thats why you have to send your shit out to get worked on. alot of you guys are BENCH EXPERTS and never done SHIT!!! im really going to listen to (100HP HONDA) next time LOL!!! can you even explain why to cut .040 off the bottom and raise the exh. port.040 and just so you know 1mm=.0394 but you knew that RIGHT!!!!!!! and the ( try to hang on) was only a expression

wow, you have absolutely no idea what you are talking about!
also, before you bash on us, maybe you should do your homework, I built my bike myself, the only work I paid for was welding, boring, and for my buddy to mod a pipe and reshape a head for me (all requiring special tooling). I ported my own jug and my bike actually is a struggle to hang onto (I'm not the only one here either). Your comment on lowering transfers to get MORE POWER is the dumbest shit I've ever heard. If you are going to come by here expecting to lay the smack down, you need to be better prepared, friend!
anyway, other than that...welcome to the board!

M.F.D.B. · Post by **M.F.D.B.** » April 23rd, 2008, 11:34 am

WoW!! Its a fuggin record!! I was going to lay the smack down on this troll, but I dont have anything origional to say after you guys stuck it to him...

Theres only one thing left to do....kill myself....HAHAHAHAHA!!!!!

:lmao::lmao::lmao::lmao::lmao::lmao::lmao::lmao::lmao:

britincali · Post by **britincali** » April 23rd, 2008, 11:46 am

blownbillybob · Post by **blownbillybob** » April 23rd, 2008, 12:37 pm

now thats what im talking about!!! this is a real live web site with real people on it YEAAA!!!!!! i new i would wake you guys up sooner or later.yea i build my own bikes to and machine my own engines.i have in my garage a CK-10,storm-vulcan RT-17y,LBB-1699,tcm25,line hone and other machine shop equipment.but anayways back to port timing,your cutting .040 from the bottom of the cyl. and .040 from the top of the exh. port.but realy all your doing is lowering the int. transfer .040 and raising the compression. by lowering the int. your closing it earlier and allowing the int. charge that got sucked out the exh. to be boosted back into the chamber by the pipe creating more static compression and better charge = more power with reeds and a good pipe it wakes up the mid and top end hit. also its closing off the int. transfer sooner and letting the next int. charge thats coming in under the piston come in sooner and for a longer duration which means your getting more charge under the piston to push up in the next int. stroke (charge) and like i said your raising the comp. so you have to modify the combustion chamber because it creates to much turbulance when it compresses the charge and detonates.you measure 15mm from the out side of the combustion chamber in and angle your tool bit holder at 75* and cut the chamber back to your mark.
i definitly noticed way more bottom end out of the bike but with the reeds and a pipe it woke it up all over the mid hits harder.i compared my 89 with all the mods to my 91 stock cyl. with pipe and reeds and it is a big difference across the whole power band not just the bottom end. and yes got much respect for GSS,LOOMIS,GORR, and you to BOB. yes its a MO Betta port job i was trying to anser a question for a hoon on the other web. and i look on this one and im gettin bagged on so what you expect, light off the fire works and stand back!!!!!!!!!!!!!!

BannedCR500Riders.com

anybody tried this port job?

anybody tried this port job?

Re: anybody tried this port job?