mopar1rules Posted April 26, 2009 Report Share Posted April 26, 2009 (edited) i run 340-350 mains. usually 350's, w/27.5 pilots, stock needles on 3rd position and 1-1/2 turns on air screws. was the bottom end hesitant at all? showing a sign of lean pilots? also, i do have a crap crank assembly for you if interested. no extra cases tho. i would be willing to be the farm, that the front end picks up on its own easily.....LOL. no need to even pull back at all, to try and make it come up....right? glad to hear you've had great results so far. nothing more rewarding after 20hrs into a port job, than to have it run sucessfully and strongly. keep up the good work. :thumbsup: now that i have my stock 26's bored to 27.1, my jetting changed a little.....32.5 pilots and 360 mains. needles left alone and i think 1-1/2 to 2 turns on air screws. Edited April 26, 2009 by mopar1rules Quote Link to comment Share on other sites More sharing options...
2003LimitedBanshee Posted April 27, 2009 Author Report Share Posted April 27, 2009 i run 340-350 mains. usually 350's, w/27.5 pilots, stock needles on 3rd position and 1-1/2 turns on air screws. was the bottom end hesitant at all? showing a sign of lean pilots? also, i do have a crap crank assembly for you if interested. no extra cases tho. i would be willing to be the farm, that the front end picks up on its own easily.....LOL. no need to even pull back at all, to try and make it come up....right? glad to hear you've had great results so far. nothing more rewarding after 20hrs into a port job, than to have it run sucessfully and strongly. keep up the good work. :thumbsup: now that i have my stock 26's bored to 27.1, my jetting changed a little.....32.5 pilots and 360 mains. needles left alone and i think 1-1/2 to 2 turns on air screws. Yeah, in fact it is difficult on the pavement to KEEP the front end down if you jump on the throttle. I wasn't even going to full throttle, maybe 3/4 at the most and it would pull the front right off the ground up through 4th, didn't try fifth yet. Okay, well maybe I'll push a little more towards full throttle then and see how it seems to like it. Going to go blast up and down the road right now, as a matter of fact! Quote Link to comment Share on other sites More sharing options...
portingjunky Posted April 27, 2009 Report Share Posted April 27, 2009 Hey i just sall your guyses porting you are doing. I was just wonderring when u guys say rays the exauhst 188* and the transfers 133* i take that u are talking about degrees if not correct me. But if so were do u set your 0 on your degree wheel? I am running Cpi inframes and 18cc domes and 35mm air striker carbs; and i was told to rase exauhst 196-198 and transfers 132-134 for a good hill/doon port. i never did this cause the person didnt tell me if this was degrees or thousandths of a inch. Could you guys please help me. Quote Link to comment Share on other sites More sharing options...
sheerider1026 Posted April 27, 2009 Report Share Posted April 27, 2009 Hey i just sall your guyses porting you are doing. I was just wonderring when u guys say rays the exauhst 188* and the transfers 133* i take that u are talking about degrees if not correct me. But if so were do u set your 0 on your degree wheel? I am running Cpi inframes and 18cc domes and 35mm air striker carbs; and i was told to rase exauhst 196-198 and transfers 132-134 for a good hill/doon port. i never did this cause the person didnt tell me if this was degrees or thousandths of a inch. Could you guys please help me. yes, it is degrees of open port timing.. you set your piston at TDC, then set your degree whell 0 mark wherever you can so that you have a reference mark on the case to go by.. hope that makes sense.. lol.. i am still learning.. those sound like some pretty radical port timings you mentioned.. sounds to be good for topend pull.. Quote Link to comment Share on other sites More sharing options...
portingjunky Posted April 27, 2009 Report Share Posted April 27, 2009 ya i did all that. and i went to 196 and the top of the piston is no were near the exauhst port. Quote Link to comment Share on other sites More sharing options...
2003LimitedBanshee Posted April 27, 2009 Author Report Share Posted April 27, 2009 First as was mentioned you have to find Top Dead Center. To do this accurately, you need a dial indicator, you have to bring the piston near top dead center, bring the dial indicator into contact with the piston and then you slowly continue to rotate the crankshaft. As the piston passes TDC the dial indicator will "stop" moving. This is TDC. The port timings mentioned are port durations, that is, how many degrees of rotation the port is open. So, to figure out the timings for cutting you take 360* - (desired duration) = X Then you take X and divide it by 2. This is the degrees of rotation after TDC that the specific port should be opening. This calculation assumes that you are only raising your port timings. Strokers and such could potentially be opening up the port in both directions. I agree with sheerider, those sound like VERY aggressive port timings. CPI's are designed as a more top end setup, so they should accomodate those timings better than some other pipes. For the record, for anyone out there, expect to spend more on tools than paying most any builder for doing the work. I have about $550 into tools at the moment, which would cover me for a decent port job, bore/hone and most of the way towards some wiseco's too. But for me, I just prefer to do the work myself. Quote Link to comment Share on other sites More sharing options...
tidos76 Posted April 27, 2009 Report Share Posted April 27, 2009 i finally got some pics of my exhaust. I'll get some of the transfers next time have the cyl off. I didnt do as much as i should have on the transfers. Quote Link to comment Share on other sites More sharing options...
toolman Posted May 2, 2009 Report Share Posted May 2, 2009 2003limited banshee How is it running ? When you use a degree wheel do you use base gaskets? If not how do you compensate for the difference? Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted May 2, 2009 Report Share Posted May 2, 2009 toolman, use your base gaskets. that way you are degreeing it in, w/how the engine would be, during its running state. Quote Link to comment Share on other sites More sharing options...
2003LimitedBanshee Posted May 2, 2009 Author Report Share Posted May 2, 2009 toolman, use your base gaskets. that way you are degreeing it in, w/how the engine would be, during its running state. Exactly, use your base gaskets, torque the cylinders down etc. just like you were going to run it. If you don't you are going to be getting inaccurate measurements. Also, I personally am running the Yamaha base gaskets, they have an absestos, although we know it isn't, like covering over them. Other than that, the bike is running strong! I am going to drop down t 350's on the mains, I have a set of 27.5 pilots I picked up and it acts like it may need the needle dropped one position. But, I am going to wait until I swap the mains, then see how the mid acts. I think I am going to make a run over to the dunes next weekend, about 3 hours away, for a day ride shake down. I've still got a few more pics to post up, but I've just been really short on time lately. Quote Link to comment Share on other sites More sharing options...
SD1026 Posted May 2, 2009 Report Share Posted May 2, 2009 where in gods name do i get fresh off the press jugs????? Quote Link to comment Share on other sites More sharing options...
2003LimitedBanshee Posted May 2, 2009 Author Report Share Posted May 2, 2009 where in gods name do i get fresh off the press jugs????? I assume you must mean, fresh 64.00mm jugs? Just have to keep your eyes open. If I remember right, these cylinders I just ported, came from a guy who ran them for just a little bit and then pulled them for a set of cubs. As far as I am aware, Yamaha isn't still making cylinders, so, as time passes, virgin bore cylinders will go away. Nothing wrong with a set of cylinders that may need a light bore and hone though. Quote Link to comment Share on other sites More sharing options...
2003LimitedBanshee Posted May 9, 2009 Author Report Share Posted May 9, 2009 Okay, got a few more pics of the build on my cylinders and a couple for another member here that I am just starting to work over. Checking the ring end gap and a view of the hone: Another ring end gap: A few of the cylinders I am starting to work over now. These cylinders should run even harder than the ones I did up for my bike. The transfers are worked over much more heavily and opened up better. I still actually want to open them up more, as they kind of narrow down as the runner approach the window. I think they look okay though. Waiting on my mock up rotating assembly to use for degreeing. Anyway.... Couple intake pics: Transfers (just starting): Quote Link to comment Share on other sites More sharing options...
SAVAGE420 Posted May 9, 2009 Report Share Posted May 9, 2009 Good job. :thumbsup: How do you like your set? Quote Link to comment Share on other sites More sharing options...
2003LimitedBanshee Posted May 9, 2009 Author Report Share Posted May 9, 2009 Good job. :thumbsup: How do you like your set? Thanks! I'm still dialing in the jetting on it, but mostly the off idle and midrange. It pulls really hard now and cranks up the RPM way faster! With the stock swinger, on the country roads I have to test it out on, I actually can't really hog full throttle on it because it will yank the front end up, pretty violently. It has a very noticeable hit on the pipe, but the hit comes early and pulls through the RPM. I've been hanging out over on PlanetSand a little more lately and several of the builders I have been talking with have recommended I try much more aggressive port timings. So, after I finish up the newest set of cylinders for another HQ member (who graciously offered them up for me to practice on) I'm going to start in on my other personal set of cylinders and give them a more aggressive grind. The other HQ member's cylinders should rip as hard, if not harder than my current ones, as the transfers are worked much better on these than on mine. I did a pretty decent job on mine, but I did a lot more looking and thinking on these, as to how much I could remove and where it was most effective. Quote Link to comment Share on other sites More sharing options...
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