porting specs?

[2strokeforever]

It would be cool if everyone that ported their bikes to post up what they did and the results
and does topend porting make mileage way worse? even if you lug it?
I basicaly want to buy a spare cylinder and make it have a cr85 ish powerband and more peak hp

dannygraves you were talking about looping out acidently with your porting if you dont mind I am very interested about what you changed to to make it do that did it take lots more gas?
does shaping the tranfers to point away from the ex port make it less thirsty?

I ride everything except dunes and mx and I love the 85/125 power delivery for TRAIL riding but its 30 hp not enough everywhere

(no that is not a typo)


x mm up x mm wider would be great

thanks

[Roostius_Maximus]

I basicaly want to buy a spare cylinder and make it have a cr85 ish powerband and more peak hp

if you want the lightswitch cr85 ish powerband then buy a new crank at the same time

lets start with whats going to support your pusuit
what do you have for:
reeds:
pipe:
silencer:
ignition:
carb:
piston:
what rads?

[powermizer]

I basicaly want to buy a spare cylinder and make it have a cr85 ish powerband and more peak hp

I may be wrong, but I think he wants you to tell him what he needs to do, to make it unridable. LOL I feel if you had a 500 that hit that hard you would have no choice but bad fuel mileage. There is no way to keep it efficient in low RPM if it has to hit that hard on top. Just my

if you want the lightswitch cr85 ish powerband then buy a new crank at the same time

lets start with whats going to support your pusuit
what do you have for:
reeds:
pipe:
silencer:
ignition:
carb:
piston:
what rads?

[britincali]

Whats the rads got to do with power delivery?

[rsss396]

If you do not have the tools to raise the transfers then I would not go over 192 degrees of exhaust duration for drag/dune

196-200 degrees of exhuast duration w/128-130 degrees of tranfer duration for drag/dune

13-15 to 1 compression ratio for race gas
15-17 to 1 for alky

more trailish i like 188 on the exhaust and would wake it up and even better if the transfers were 126-128 to go with it

[Roostius_Maximus]

Whats the rads got to do with power delivery?

heating like a bastard

[2strokeforever]

I dont have a 500 YET, but its being sent to me from service honda in 2 days

brand new AF stock except:
PC pipe and spark arestor
39.5 PWK? I think it comes with it?
I plan on copying bearoso's fan idea, already got the regulator and fans
also want to be able to run pump gas

if you want the lightswitch cr85 ish powerband then buy a new crank at the same time Wink

my cr80 didnt have a lightswitch power band maybe because I wieghed 90 lbs and could jet it perfectly, once in the morning and once at lunch

does that mean someone makes TI cranks? or do you mean just balanced? or that it wont last?

What is stock cr 500 port time area? I would measure it if my bike was here
will It work good if I copy the cr 80 port time area as close as i can?(I doubt it, but cant hurt to ask)

[Roostius_Maximus]

i just mean to make sure you have a new crank if you're going to try and turn the piss out of it
sounds like you're decent on parts
stock reed? lets hope so

You'll have the R casting head, its wide squish with a narrow+ tall pocket, and alot of quench, too much. have someone cut "the 3rd angle" into that head to narrow the squish and then face it down to achieve a tighter squish.

So this will be a standard bore jug with an oem piston? Use it
or will you be trying to use the jug with the markings on the exh floor? be cautious to not make the port lower so the intake charge breathes under the piston skirt

[LOVEMYCR500]

my motor is at 186 exhaust and 131 on the transfers, I had the transfers set at 128-130 but I ended up having to raise my cylinder up after the fact once I realized I got the exhaust floor a bit low and my piston was going to free port. Probably doesn't rev quite as good as it could with the transfers this high but I have a little room to raise the exhaust up if I want. I want a broad power band and this motor does have this now compared to stock.

Running 14:1 compression on race fuel, head and squish has been cut, PC pipe, v-force reeds, stock PJ carb bored running the stock 93 ignition. Looks like the jettings going to be 55 pilot, DGL needle 4th clip and a 170-172 main.

[dannygraves]

my old gen-1 was a serious gas guzzler, but pulled real well up top, can't remember all the specs, there is a thread around here somewhere with all that, I believe I went 190*ex and 130*in drilled extra boost ports, opened up existing boost ports (as dewayne put it, big enopugh to stick your thumb through) raised and broadened the upper boost port, cut window in piston, widened exhaust to the limit. ran a mikuni tmpro41 vforce2 and fmf fatty until I got my dewayne modded pipe. The mikuni was runng a 50 pilot, 370 main, 100 power, fm46 needle 3rd clip and r-6 needle jet.
I kept the compression relatively low to keep more power up top.
She was an uncontrolable beast and NEEDED swingarm extensions. I sold it to a guy in montana who hill climbs, haven't heard from hiom, hopefully the bike didn't get the best of him.

[2strokeforever]

fmf fatty until I got my dewayne modded pipe

did that make a big difference?

[dannygraves]

the fatty was a huge difference! DeWaynes pipe was basically a gnarly that was modified to perform like a fatty only better, I couldn't tell the difference between a fatty and dewaynes pipe, the the both compared to a PC or a Gnarly, it was very noticeable.

[Roostius_Maximus]

only thing with dewaynes pipes is that they dotnt fit worth a fk
I have one of those gnarlys by dewayne here, cant fit it on a steelie, gen 1 or 3. even tried pulling it on with a rachet strap.
he pushes all the "dents" out of it for more power, but you have to go put them back in to get arround the jug+reed.
it wouldnt even fit on an engine sitting on the bench
we have the hprny shortened pc silencer for it too, looks cool but sounds like crap and makes no torque

[2strokeforever]

danny do you have pictures of the extra boost ports or a picture of something similar. all the pictures in your old thread show up as tiny x s

[dannygraves]

yeah, some fag fucked up my hostig space for me
I don't know if I have any pics of mine, but Brit's GSS jug is where I got the idea, dig, there are pics of it in a very old thread.
in hind sight, I don't think I would drill those again though.

[rsss396]

Ya I have always thought that those extra boost ports are so high up that during the time the ports are open the intake port is wide open so I can't see allot of extra flow into the crankcase.
but they look cool!

[Roostius_Maximus]

theres other boost ports out there that work better and are not so hard on fuel. takes some welding, but works

[rsss396]

Here is a picture of the boost ports and a extra port added to the floor of the intake that feeds behind the sleeve.
You have to look close on the right side of the picture to see it.
I found this picture a while back any thought the port that feed behind the sleeve would be something to try.

[glen howell]

Those ports are there for a reason,They help bring back the low to mid range.The ones that can be put in by extra welding we have tried but they don't work as well. The problem is doing either one of them , requres the skill in welding and the having a flow bench to get the angles right ,Just copying from a picture is not easy to do ,and to get it right. Again it's not easy to copy a port job from a picture. I don't recomend it for a layman.to try if you get it wrong you might not be happy. Remember a CR-500 will outrun and out accelerate a CR-85 in third gear take offs and I'm sorry for the extra gas milliage loss but if done right most want complane. more to this dribble DEWaynes mod on the FMF pipes works very well.Glen

[Roostius_Maximus]

I'm sorry for the extra gas milliage loss but if done right most want complane. more to this dribble DEWaynes mod on the FMF pipes works very well.Glen

I dont doubt that for an application that needs that porting the fuel econlmy is irrelivant
Dewaynes pipe was likely a decent thing, this one he did cant even be installed on an engine loose on the bench tho.

[dannygraves]

my dewayne pipe fit the 2nd time around and was actually on the gen-1 when I sold it.
Glen, you are right, before I drilled the holes I was very peaky with a lot less bottomend, after adding the holes, the bottomend came back and came back hard. You are also right in that it is very hard use pics to judge by since when I drilled mine, no matter how careful I was they exited at different points and that ultimately caused my piston to seize on only one side. afterward I realised the problem and reshaped the exits to match. I personally would not drill the holes again, especially for dunes riding, I thought the bike rode better in the sand being peaky with less lowend and more topend mostly because it was just plain hard to control.

[glen howell]

If those ports are installed right and the angles are right you will get more top o/rev and still have good bottom and mid range also.The new race porting is doing very well so far we've had one 3rd. place against 4 cyl.600 cc bikes, and one 1st. place and fast time of the day against 0-700 cc bikes,In drag racing 1/8 mile 6:46 et. at 93 MPH against 0-700 cc bikes,So far the riders are happy.They have the extra ports in them but again these are PRO. riders and will get more out of the engine because they either blow or go as they don't have to pqy for repairs ,but so far the engines are holding up very well. Rooosty if that pipe don't fit I bet if you sent it back to DE WAYNE he would make it fit right .Glen

[dannygraves]

Rooosty if that pipe don't fit I bet if you sent it back to DE WAYNE he would make it fit right .Glen

yup, I threw mine across my driveway and before it stopped sliding I was dialing his number. I sent it back and he fixed her up right, I still had to finess the pipe on a bit, but it did fit and ran well.

[ellett]

I basicaly want to buy a spare cylinder and make it have a cr85 ish powerband and more peak hp

Dude, my port work makes power just like a CR85....

x mm up x mm wider would be great

I don't know what the measurements ended up being. You want me to tear it down and check?

[dannygraves]

looks like the dude took the leather codpeice from the movie "Seven" and fucked that cylinder to death