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Author Topic: Tuning.....of course  (Read 1100 times)

Offline FloridaRiderSG

Tuning.....of course
« on: October 07, 2018, 04:44:39 PM »
Hello guys, Im Shawn and I just got an 86" a few months ago for the track for when I moved to Florida. Someone else built it, it was never ridden just broken in and he thought the tuning was "close", so I wanted to try to get it best as possible before hitting the track. Been here for 5 weeks and got my R on a dyno finally. Been a long time since I had a 2 stroke and I was never very good at tuning. Its a 330 esr, trx-5b pipe, ?carb?. I ended up getting it real close but there was so many people around and I was getting rushed because others wanted the dyno (was at a bike shop special event) I wasnt thinking clearly so I didnt get it perfect. I have 170 main, needle 4th clip down, 50 pilot. It was lean at idle (which I believe turning the air screw in should solve?) but he was bringing it to 4000 rpm then hit it full and it would lean out from there until 6000 then level off. Do you think its just getting to much air and the air screw again will solve this? Also it would just be a little rich all the way up 9500, but I was kinda happy about that, if I take air away will that lean it out up top also?

Thanks guys, sorry if you need me to explain it better, just say.
« Last Edit: October 07, 2018, 07:45:47 PM by FloridaRiderSG »

Offline The norm

Re: Tuning.....of course
« Reply #1 on: October 07, 2018, 06:23:15 PM »
I'm assuming you are at sea level? 170 main on a 330 with a 39pwk seems lean. I have a esr 310 cylinder and a 38mm airstriker carb with 52/185 jetting and 3rd groove on a dgh needle. I like to keep my air screw at 1.5 turns when getting the pilot set so as conditions change I still have adjustment room. Maybe Gene will chip in a little insight. He has a 330. Good luck, Loren
I had a BDT motor once.....It SUCKED!
Currently: Hybrid Engineering 310 stroker built by Pete

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #2 on: October 07, 2018, 07:10:46 PM »
I'm assuming you are at sea level? 170 main on a 330 with a 39pwk seems lean. I have a esr 310 cylinder and a 38mm airstriker carb with 52/185 jetting and 3rd groove on a dgh needle. I like to keep my air screw at 1.5 turns when getting the pilot set so as conditions change I still have adjustment room. Maybe Gene will chip in a little insight. He has a 330. Good luck, Loren

Thanks for the reply.

Is there anyway to see if mine in fact is a 330? Im going to see if the cyclider is marked, I did not build it. It put out only 45 horse, but it was with holeshots, the guy said with street tires he figured around 50.  Seems all the 330's are around where you are main jet wise. Not sure why my main is so much lower. It was just a little rich up top with a 170.......maybe the needle on 4th clip made a difference?

Again thanks, hopefully more people will chime in.

Shawn

Btw I cant believe I got my R on a dyno and I bungled it so bad.
« Last Edit: October 07, 2018, 07:12:22 PM by FloridaRiderSG »

Offline jwraymond6

Re: Tuning.....of course
« Reply #3 on: October 07, 2018, 07:20:05 PM »
I'm assuming you are at sea level? 170 main on a 330 with a 39pwk seems lean. I have a esr 310 cylinder and a 38mm airstriker carb with 52/185 jetting and 3rd groove on a dgh needle. I like to keep my air screw at 1.5 turns when getting the pilot set so as conditions change I still have adjustment room. Maybe Gene will chip in a little insight. He has a 330. Good luck, Loren

Thanks for the reply.

Is there anyway to see if mine in fact is a 330? Im going to see if the cyclider is marked, I did not build it. It put out only 45 horse, but it was with holeshots, the guy said with street tires he figured around 50.  Seems all the 330's are around where you are main jet wise. Not sure why my main is so much lower. It was just a little rich up top with a 170.......maybe the needle on 4th clip made a difference?

Again thanks, hopefully more people will chime in.

Shawn

Btw I cant believe I got my R on a dyno and I bungled it so bad.

When referring to the needle are you 4th grove  from top or bottom of the needle
87 363 sphynx built by Pete @ hybrid engineering

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #4 on: October 07, 2018, 07:46:58 PM »
Yes 4th down. Now that I think of it Im wrong on the carb, I have to take it off, I never checked Im not sure why I thought 39.

Offline The norm

Re: Tuning.....of course
« Reply #5 on: October 07, 2018, 08:13:01 PM »
I assume that you have an "O"ring head. Take that off and clean the top of the piston. There is a part number on top which has the size. 76mm is a 330 I think?
I had a BDT motor once.....It SUCKED!
Currently: Hybrid Engineering 310 stroker built by Pete

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #6 on: October 07, 2018, 08:31:34 PM »
I assume that you have an "O"ring head. Take that off and clean the top of the piston. There is a part number on top which has the size. 76mm is a 330 I think?
OK appreciate the info.

Online hickwheeler

Re: Tuning.....of course
« Reply #7 on: October 08, 2018, 12:01:01 AM »
My 330 +5 stroke I have a 38 as carb, dgh needle middle clip, 52 pilot and I think am 195 on the main. I'm a little rich all over. But left it that way after having issues my last time out.
88 ESR 330 5mil stroke
88 ct350pv (BOF Build)
Puma coming soon

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #8 on: October 08, 2018, 09:16:43 AM »
OK so here's the max power and air to fuel. He was rolling it from 4200 to 4400. The blip at the end was him.

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #9 on: October 08, 2018, 09:20:51 AM »
My 330 +5 stroke I have a 38 as carb, dgh needle middle clip, 52 pilot and I think am 195 on the main. I'm a little rich all over. But left it that way after having issues my last time out.
Im right there with you but far off with the main jet. Sorry for sounding stupid but with more stroke do you need more gas? More stroke =more displacement=more gas ?
« Last Edit: October 08, 2018, 09:43:43 AM by FloridaRiderSG »

Offline 2Nubs

Re: Tuning.....of course
« Reply #10 on: October 08, 2018, 10:20:42 AM »
You're right Shawn. I believe his setup is a 330 cylinder with a +5 stroker, which is around a 350cc of displacement.

I can't say for sure if yours is lean or not based off the jet number, but on a 185 main, mine is very rich. So you may not be too far off.

Does it seem to be running solid now? Did the person tuning/running the dyno mention the lean spot on the AFR graph?
86 330

Offline 2Nubs

Re: Tuning.....of course
« Reply #11 on: October 08, 2018, 10:34:25 AM »
I believe it would be a good time for you to do some plug chops. The tool to chop the spark plug is about $15. You can do a few of those proper and post some good pics here and get some help reading the plugs. That will tell you what is going on inside the cylinder.
86 330

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #12 on: October 08, 2018, 12:24:40 PM »
You're right Shawn. I believe his setup is a 330 cylinder with a +5 stroker, which is around a 350cc of displacement.

I can't say for sure if yours is lean or not based off the jet number, but on a 185 main, mine is very rich. So you may not be too far off.

Does it seem to be running solid now? Did the person tuning/running the dyno mention the lean spot on the AFR graph?
Yes he did but didnt really have an answer and kinda had enough and had people waiting. Im thinking maybe the air screw needs to go in a half turn, it was very lean at idle also.

Offline FloridaRiderSG

Re: Tuning.....of course
« Reply #13 on: October 08, 2018, 12:26:32 PM »
I believe it would be a good time for you to do some plug chops. The tool to chop the spark plug is about $15. You can do a few of those proper and post some good pics here and get some help reading the plugs. That will tell you what is going on inside the cylinder.

Ok I have plugs and was thinking about taking some where for a ride to see how it feels. I haven't even rode it yet....at all, just around a dirt parking lot in NY and up my road here quickly.

Offline 2Nubs

Re: Tuning.....of course
« Reply #14 on: October 08, 2018, 12:42:57 PM »
There is a method to tuning the air screw. I believe it may be in the Duncan Racing link I sent at one time. If the air screw is below 1.5 turns or over 2 turns when idling the highest you need bigger/smaller pilot jet, respectively.
86 330