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marpolsdofer

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About marpolsdofer

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    TT Newbie

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    Iowa
  1. marpolsdofer

    1981 Yamaha XT250 No Start

    I have not drilled out that area yea but I dont think it does anything on the 500. Then again maybe it does. There was a plug on the side and I drilled it out. I found a air screww behind it. The drill messed up the head so I had to dremel a new head for it. However the oring was shot and cant find one that fits without the screw getting stuck. Now you cant order them for the XT or the SR that use the same carb style (just little bigger) for the 500's. Smaller sizes use diffrent carb style or setups. That is why you dont have a lower diaphragm or one on the side. However, the TT does use the same air screw that you can order just a diffrent style carb.
  2. marpolsdofer

    1981 Yamaha XT250 No Start

    Never mind the carb on the 250 vs the 500 are diffrent. In the carb you should have 3 Diaphragm's. One on the side with the 3 screw cover theal looks like a triangle, one for the accelerator pump on (square cover with lever), then another on the bottom of the float bowl (square cover). Each one has a spring behind or front of them. Each spring being diffrent lengths and sizes. The bike I am working on is a 500 but the carbs should be the same just diffrent size. Spings are 35, 57, and 70 from what I see on my parts diagram. I just need to see what yours look like to see if mine are the right ones and in the right location. http://www.masoncitypowersportsinc.com/OEMpartfinder.htm#/Yamaha/XT500G_-_1980/CARBURETOR/XT500G_%281980_MOTORCYCLE%29/CARBURETOR_%28XT500G_-_1980%29
  3. marpolsdofer

    80 XT500 carb problems

    So I am have some problems understanding the carb on this bike. The parts diagram does not show any thing about any type of mixture scews but it does show the accelerator pump and it components. That being said the repair manual does not show any accelerator pump or its components but it shows a mixture screw. That carb I have is just like the one on the parts diagramm. I just got new parts for this carb and cleaned it pretty good. After we got it put together had a little trouble starting it but once we did had no problems after that. Now the problem is the bike is idling high about 4 k. I did not adjust anything but the accelerator pump. Even then I put it back how I found it like when it was working normal before the rebuild. New jets, needle and seat, diaphragms, gaskets, cleaned the carb that was it. Also new fuel lines, fuel filter, air filter. Fuel is new as well. At first it did not idle that high but after a few min of riding it started to this. After looking at the plug it was weet and black. I did not find any air leaks by looking but I will have to do a smoke test. Anyone got any ideas?
  4. marpolsdofer

    1981 Yamaha XT250 No Start

    Can you take a pic of you diapham spring? I want to make sure I have the right ones in the right spots.
  5. marpolsdofer

    Timing Advacment? 79 yz 250

    So the timing for the bike according to the manual say 1.37mm (.054 in) I think is in the 2-3 BTDC (forgot mag size to calculable it will do it later and my timing light was being a pain with the CDI). The bike seemed to run awfully rich that way and to make the story short I ended up as far advanced as it would go. Response was a hell a lot better, but it still was rich and dying at on idle. (this is after a bunch of carb work to fix the issue) Fast forward I got to thinking that it was not the carb but that I was burning gear oil from the case after seeing several things Tore engine apart and all the clues and suspicions led me to be correct. Getting ready to put it back together on Monday and would like to know if anyone knows any better timing setting? Running 91 octane, 32:1 mix, DG pipe, UFO in the carb, and Boysen read valves if that helps anyone. Anyone know the compression ratio?
  6. marpolsdofer

    Timming Advacment? 79 yz 250

    So the timing for the bike according to the manual say 1.37mm (.054 in) I think is in the 2-3 BTDC (forgot mag size to calculable it will do it later and my timing light was being a pain with the CDI). The bike seemed to run awfully rich that way and to make the story short I ended up as far advanced as it would go. Response was a hell a lot better, but it still was rich and dying at on idle. (this is after a bunch of carb work to fix the issue) Fast forward I got to thinking that it was not the carb but that I was burning gear oil from the case after seeing several things Tore engine apart and all the clues and suspicions led me to be correct. Getting ready to put it back together on Monday and would like to know if anyone knows any better timing setting? Running 91 octane, 32:1 mix, DG pipe, UFO in the carb, and Boysen read valves if that helps anyone. Anyone know the compression ratio?
  7. marpolsdofer

    carb settings 79 YZ 250

    I know here are people who have done this befor.
  8. marpolsdofer

    Carb setting 79 yz 250

    My race sled has dual carbs and even they have standard calculated setting depending on temp, hunitiy, elevaton, ect. It seems more easy to figuer out. I am just asking what other people has done and tried so I can make this quick and cheap. Cheap I mean not buying 3-4 pilots and needls then send them back what I dont need. Quick becaues takes time gettong that carb in and out.
  9. marpolsdofer

    Carb setting 79 yz 250

    Well I understand how to do it. I am asking becaues when I did a google search it showed talks about it from few fourms from here and vintage one. In the talks they was talking about changing the pilot jet and neddle but they did not mention witch ones only the stock stuff. Also starter jet maybe as well. As for how it runs stock. I only got to ride it for about 30 min befor I had to put it away 2 weeks ago and head to Ft. McCoy and gone untill satuerday. The carb is over flowing since the needle and seat are bad with is making it extreamly rich right now.
  10. marpolsdofer

    Carb setting 79 yz 250

    Anyone please?
  11. marpolsdofer

    carb settings 79 YZ 250

    Anyone please? Anyone please?
  12. marpolsdofer

    Carb setting 79 yz 250

    Also running 91 32:1 at 1000ft
  13. marpolsdofer

    carb settings 79 YZ 250

    Also running 91 oct, 32:1 mix, elevation 1000 ft.
  14. marpolsdofer

    carb settings 79 YZ 250

    I have a 79 yz 250 I just finished restoring last week and got some time to ride it befor it rained and I had to leave for AT for the Army. Right now its overflowing so I am going (fuel is shut off while I am gone) so I am going to get a neddle and seat for it but plan on ordering all the jets, needles, any thing els that need to be changed from stock. Right now it has all stock jets and needle. I am running a DG pipe, packed muffler and Boyasen reeds currently. What has others used for the best proformance. Since I am gone from home I want this stuff at my door when I get home and dont have much time to be waiting around everytime I get the getting wrong not to mention the money waste. I know the stock setting and it at there right now. Main jets is a none issue since I have the whole 400s and down to 380. If any one know the best option to make it better over stock with the mods let me know.
  15. marpolsdofer

    Carb setting 79 yz 250

    I have a 79 yz 250 I just finished restoring last week and got some time to ride it befor it rained and I had to leave for AT for the Army. Right now its overflowing so I am going (fuel is shut off while I am gone) so I am going to get a neddle and seat for it but plan on ordering all the jets, needles, any thing els that need to be changed from stock. Right now it has all stock jets and needle. I am running a DG pipe, packed muffler and Boyasen reeds currently. What has others used for the best proformance. Since I am gone from home I want this stuff at my door when I get home and dont have much time to be waiting around everytime I get the getting wrong not to mention the money waste. I know the stock setting and it at there right now. Main jets is a none issue since I have the whole 400s and down to 380. If any one know the best option to make it better over stock with the mods let me know.
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