Eric Gorr Porting

[green_passion]

I finally got my cylinder back from Eric Gorr today and she's purrrty!!

Here are the pictures:

[canyncarvr]

An 'inthread' comparison:



Considerable differences..although I can't pretend to say what they will amount to performance-wise. Yours looks to be considerably smaller area-wise...look at the center port!

I wonder what his like-ported (to the same end) 200 cylinder would look like. Considerably different I would suppose.

What was it you asked for again, please? Moh Better? Or...

No exhaust port pic? Was it raised, or left alone?

Those are some considerable hone marks!

THill got his cylinder from Langcourt. Hope he gets some pics up.

Thanks!


I'm looking forward to your impressions of the whole setup!

[skipro3]

I kind a thought the hone marks look to be agressive! That must have a pretty thick plating layer in that cylinder.

[Jeb]

What do the marks on the cylinder walls "feel" like - can you feel them? Even if the lighting is shining funny they almost look like gouges . . .

[canyncarvr]

Langcourt told me they could plate to a thickness something like .070". Yes, I understand Langcourt didn't do this cylinder.

It's a good time to consider your break-in method. Such an agressive hone would benefit from a 'hard' break-in imo...then, I do have a biased point of view. My experience with that break-in method is it works very well.

[green_passion]

What do the marks on the cylinder walls "feel" like - can you feel them? Even if the lighting is shining funny they almost look like gouges . . .

Very smooth actually. Matt was moshing on it last night to get it back together but he was missing two seals that he's picking-up today. I'll have a ride report after this weekend about the bike.

EG did porting work to to help out on the mid to to top, replated the cylinder and then honed it to make sure it matched the piston. (He was also suppose to perform the head mod too but it didn't get done for some reason although we requested for him to.)

It'll be interesting to see how much of a difference it makes!

Oh and as far as break-in, it'll probably be a quick ride around the camp and then pin it down the bomb run at the races this weekend.

[canyncarvr]

One of the problems with USChrome's replate has been 'flashing' (don't know you call it that ..leftover's from the replate process) junk in the RH KIPS actuating shaft bore. Might want to 'specially look at it..make sure that rod moves freely.

NOT doing so has caused problems for some.


Well...one, anyway.... that I can think of.

[jc7622]

i hope you don't mind a quick related hijack between now and your ride report


Has anyone ever heard of Wes Gilbert of Boyesen Precision Porting? I had him recommended to me on another site. Evidently he used to work with Eyvind Boyesen or maybe still does. Below is a link to a thread where he and Eric Gorr exchange info.

http://www.dirtrider.net/forums3/archiv ... -5273.html


I also came across this tool recently -

http://www.buxtools.com/index.php

[canyncarvr]

Installing wrist pin C-clips in pistons is the engine rebuilder’s worst nightmare.

If I classed that process as a 'worst' nightmare...I guess I wouldn't have too many of 'em.

I don't see a $$ for that part. How much is it?

Aha..$45.50 I see on another site.....

[Indawoods]

er... couldn't you make that tool yourself for like a dollar?

[Knucklehead]

The mechanic chiming in here.

As for the porting Eric straighten the transfer ports, raised the exhaust ports and cleaned up the intake ports. The intake porting is nowhere near as radical as FRP, but as a result we have a much stronger bridge in that port. Eric feels there is not much needed to this cylinder porting wise. After all do you need any more bottom end from a 220? Top is another issue. The weak link there is that 33mm carb. The RB carb mod should really wake up the top-end, which is where this motor lacks. As for the head I told Eric I wanted to run pump gas, he felt stock compression was about right and left it alone. Again trying to pick up power on mid to top not the bottom so the higher compression was not needed. But after hearing all the praise about RB's head mod's we will probably give that a shot in the very near future. I know some of you have asked why not send the head to RB to begin with? Well at the time I sent the cylinder off I was un-sure what the game plan was going to be. The cylinder had a couple gouges in it. I was not sure if it was going to be welded, and replated or bored first oversize and replated. So if the bored size was increase I needed the head to be machined to match. Luckily Eric repaired the cylinder and we got to keep it stock bore. As for plating getting into the exhaust port, Eric had warned me already to check to make sure it all moves smooth, since I did not send him the exhaust valve like he prefers. Either way he got it all cleaned up and it works just fine. And lastly the honing looks perfect, and in-line to what I would expect from 240 grit. Must just be the picture making it look more than it is. Even so what's a little extra oil retention going to hurt

All in all I'm once again happy with the work provided by Eric Gorr. He has done a few of my CR250 cylinders and will continue to get my business as long as he is doing the work.

[Indawoods]

I think the RB head mod increase power throughout the band... just much stronger all the way to the top. That is my impression anyway... was a nice addition to the carb's attributes.

[2001kdx]

Did ya install 'em separately vince?

[Indawoods]

Yes... carb first.... about a year later, the head.

[canyncarvr]

Re: 'As for plating getting into the exhaust port...'

That's not a reference to anything I said, I presume? I mean...I didn't say anything about plating in the exhaust port...

No matter. I brought it up more as a matter interest for the casual reader...not a chiming mechanic.

....

I s'pose that wouldn't be near as bad as a rhyming mechanic...

[fuzzy]

Looks nice! BIG difference between that and CC's FRP cyl!

RB head mod would still be recommended. It's not quite 'more compression,' but the shape/angle of the squish band. EG probably doesn't do that many KDX motors, and I can understand being leary of ruining the 'pump gas' requirement. RB has a lot of experience on this specific head.

[ebeck]

Looking for a ride report. I guess she got it bck together and moved on.

You'r saying the FRP porting is more agressive? Is the canyncarvr picsure an FRP port?

I looked at a spare 220 jug I have and the EG intake in the pics at the top looks almost identical to the stock jug.

Curious how porting alone affects mileage.

[green_passion]

Looking for a ride report. I guess she got it bck together and moved on.

Naww...haven't moved on. I'm just waiting to get some serious seat time in the bike. It seems to be a constant comedy of errors with that bike since I got it all put back together. (Lost kick-starter bolt, blown rear shock, fouled plug, blown head gasket, etc. )

What I can do is give you my impressions so far...

My first ride on the bike was at a race in May. Instantly I was impressed with the improved responsiveness of the throttle. It truly is awesome!! The second thing I noticed was how much easier it was to kick the bike over from before. (Yeah, I'm a girly-girl that way! ) Once out on the race course and wide open, the bike was like a whole new machine on the top end!! It was able to pull my arse around 100% better than before. Once we hit the first hill, I had my first disappointment about the performance of the bike. I found that I had lost some of the bottom-end that I loved so much. I had to down shift into first just to make it up a small hill and abuse the heck outta my clutch just to barely make it up. *le sigh*

Although that was a minor setback, I was still happy overall with the performance of the bike. Plus at that point we still needed to install the Boysen power reeds and have the head mod done by RB.

Since then, we've had the head mod performed & reeds installed. My first race on the bike with the last (hopefully) of the upgrades, the bike felt great and the uphill issues seem to be a bit better. Still have to fight it a bit but with the new rear shock it seems to track *A LOT* better. Going through the rocks was a breeze compared to before when my back-end was all over the place. SO my suspension is all dialed in and now I just need to actually ride the bike for longer than about 25 miles to give you a more complete riding report.

My hope is to give a more complete riding report after we hit Kennedy Meadows the weekend of July 12th - 14th.

Cheers!

[fuzzy]

DFIII reeds will be even better for your lost low-end. Is your carb done? Leaking head gasket won't help either.

[canyncarvr]

Re: 'Is the canyncarvr picsure an FRP port?'

Yes. My '00 200 cylinder. Ported for woods riding (exhaust port was not modified), pump fuel.