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looks good man.. got a pic of the transfer ports after you cut them?? when do you plan on having these bolted on and running?? i wanna hear how they run.. good work.

 

Of the transfer ports, as far as timing you mean?

 

033.jpg

 

GoodmarkandPorting008.jpg

 

You can kind of get an idea in these pictures. I spaced getting pics of both cylinders side by side after the timing was changed, but of course it won't show a lot of comparison, but I can snap some.

 

As far as running, I'm going to make a couple dyno passes next week with the stock cylinders first, waiting on base gaskets from the Yamaha shop, to bolt these up. Realistically, I might be able to get some dyno time on Tuesday with stock cylinders and maybe make passes with these on Friday. That's my ambitious timeline.

 

Thanks for the compliment...

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yep, wanted to see the transfer ports (duration).. so is this going to be a hot woods/dune port?? the cuts look nice.. i assume you used a degree wheel.. did you use a base gasket under the jugs when you degreed and marked your cut-to lines?? i have a set of jugs that i could do some more work to also.. they are just a little more than a cleanup port done to them.. i didn;t know you could do the bost port at a different timing.. i can see the theory behind it also.. well keep us posted.. i am anxious to hear how they run..

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Do ya get em from CC Specialty? Most use the cross cut (diamond cut) in the 1/8" carbide and the single (spiral cut) in the 1/4" and of course the 1/4" hogs are single cut. Just wondering where ya get your carbide.

 

 

Yes, i have bought them all at cc specialty. If you are the girl who answers the phone i have talked to you more than a few times. :biggrin: I cant remember the handpieces ive got exactly but the mc1 is one for sure. Also got the vise and other stuff as well, i plan on buying more stuff in the future when i graduate and get a job! lol

 

 

the porting looks pretty good. A few things i would try is get a smaller round tree or ball shape 6"x1/4" bit and make the "curve" of your transfers better. Where you can see that you havent cut yet needs to be. Make it all on the same level if at all possible. If it were a set of cylinders i was porting i would polish the exhaust more, its up to you and looks ok but id spend some more time on it. What grit did you finish with?

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Yes, i have bought them all at cc specialty. If you are the girl who answers the phone i have talked to you more than a few times. :biggrin: I cant remember the handpieces ive got exactly but the mc1 is one for sure. Also got the vise and other stuff as well, i plan on buying more stuff in the future when i graduate and get a job! lol

 

 

the porting looks pretty good. A few things i would try is get a smaller round tree or ball shape 6"x1/4" bit and make the "curve" of your transfers better. Where you can see that you havent cut yet needs to be. Make it all on the same level if at all possible. If it were a set of cylinders i was porting i would polish the exhaust more, its up to you and looks ok but id spend some more time on it. What grit did you finish with?

 

In that last pic of the transfers, that was actually early on in the cutting, that was just the only picture I had that showed the change in timing easily. I've since gone back and worked over the transfers from tons of angles. It was weird, just when I thought I couldn't get to some part, I'd rotate the cylinder and see a new way in. The transfers were worked from the base with some long burrs, with the 90* 1 MC, and with my Foredom #30 handpiece and various 1/8" burrs from the top of the cylinders. I'll take some better pics looking down the transfers from some of the same angles to see how the pass review, but I didn't give myself a good representation of the end product with those pics.

 

The exhaust was only finished off with 200 grit; you know I wasn't sure. I've heard mixed reviews about how extensively it really needs to be sanded/polished. It'll be easy enough to jump back in and polish a bit more.

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yep, wanted to see the transfer ports (duration).. so is this going to be a hot woods/dune port?? the cuts look nice.. i assume you used a degree wheel.. did you use a base gasket under the jugs when you degreed and marked your cut-to lines?? i have a set of jugs that i could do some more work to also.. they are just a little more than a cleanup port done to them.. i didn;t know you could do the bost port at a different timing.. i can see the theory behind it also.. well keep us posted.. i am anxious to hear how they run..

 

Thanks again... Yeah, the specs were recommended to me as a dune port spec. But it does have 30* of blowdown to help compensate for the increase in the exhaust port duration and bring some bottom end back. Again, the specs were not of my genius, Dan Wade recommended them to me, including te boost port timing. His theory was that it helped with scavenging in the top end of the cylinder. Hopefully next week I will have dyno numbers to put these theories to the test.

 

Yes, degree wheeled for timing. I'm going to mark my current cylinders right before I pull them off, for an even more aggressive dune port, to pair up with some CPI's and bigger carbs. Just need some CPI's now...?

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These pictures should give you a better idea of how the transfer port runners were finished off. Sorry for the confusion caused by the old pic, but I definitely would not have left those runners looking like they did in the timing picture up above. Hopefully these should give you a better idea of the extent to which I worked the transfer runners over:

 

006.jpg

 

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005.jpg

 

007.jpg

 

010.jpg

 

What does anyone think about moving the back wall of the aux transfers back? I.e. wrapping the cut-away farther around the cylinder towards the intake to open that runner up?

 

Oh, and XxMeltIcexX had said to take more out of the exhaust, where at? The timing is about as aggressive as I want to get it with my current setup and I'm at 69.xxx% width:bore ratio? Do you mean farther down the port, towards the "nipple"? I was hesitant to hog that out too much because I didn't want to compromise my exhaust velocity? Am I screwed up here?

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I don't really know what you are talking about or what I am looking at, but it looks good....lol. I'd like to learn about this kind of stuff though. What exactly do those values mean? Is there a resource online that gives detailed explanations? Someone is sellin CD's on ebay that supposedly teach you porting. Anyone ever check them out?

I almost pissed my pants laughin' so hard at the 1st sentence in your post...thanks, man!! :biggrin:

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about moving the secondary/aux transfer back wall, back even more, to make it wrap around more on the intake side of the piston, might not be a good idea. you'll have to watch out for the ring end gap and ring stop pin, from getting exposed into the port window......i believe. anyone, please correct me if i'm wrong.

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about moving the secondary/aux transfer back wall, back even more, to make it wrap around more on the intake side of the piston, might not be a good idea. you'll have to watch out for the ring end gap and ring stop pin, from getting exposed into the port window......i believe. anyone, please correct me if i'm wrong.

 

Trying to make sure we are talking the same line here. I'm not planning to change the aux transfer port window any, just the runner. I.e. the track coming from the base of the cylinders leading up to the actual port window.

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I think if you were to move that wall back would increase turbulence where the intake is trying to turn that corner and go out the transfer exits. You want the smoothest flow, which is helped by reducing the radius of that corner, so Id leave it. But what do I know, haha

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Trying to make sure we are talking the same line here. I'm not planning to change the aux transfer port window any, just the runner. I.e. the track coming from the base of the cylinders leading up to the actual port window.

 

oh, your talking about the runner.....LOL. i was thinking you were going to move the port window itself. woops.

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I think if you were to move that wall back would increase turbulence where the intake is trying to turn that corner and go out the transfer exits. You want the smoothest flow, which is helped by reducing the radius of that corner, so Id leave it. But what do I know, haha

 

 

Okay, I get what you're saying. Move that back wall farther back and the airflow has to "bend" even farther back to make the run down; makes sense! You must have some background in porting based on your post? Not trying to offend, if you do a lot of work and I don't know, sorry...

 

How about the earlier comment about needing to take more out of my exhaust. Ideas/opinions?

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I dabble....haha. Too many engineering classes I guess.... About the exhaust- If you have your port timing where you want it and have it blended through to the exit and polished somewhat you should be fine. I dont think increasing that inside diameter is going to net you alot of numbers, if anything it will reduce exhaust flow velocity and take away some bottom and mid rpm power. Also you wont gain anything if the I.D. of the exhaust port is significantly larger than the I.D. of your expansion chamber inlet. (more turbulence, less flow, less power)

 

EDIT: theres some cpi pipes in the for sale forum that popped up today, better hurry!

Edited by austin
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