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Thread: Sl650 reeds

  1. #1
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    Sl650 reeds

    Upon inspection of the reeds in my 650, I found a few corners to be slightly chipped, however it looked as though they would still seal. Could this be causing the engine tuning problems I am having? I have gone through every part of the fuel system and everything is immaculate. It runs great from about 3/8 throttle to wide open however I am having problems with the low speed operation. It bogs when I open the throttle from idle to about the 1/4 throttle area. Once it gets to about 3/8 throttle or so it works great. I have read the mikuni manual, and I have ordered the next size bigger low speed jet. my 94 SL650 has 75 low speed jets, and I am going to try 77.5s. I noticed the 95 SL650s specify 77.5 low speed jets. It idles great, but I have backed out the low speed screw to try to help throttle response, but with this adjustment, its too rich when sitting at idle for a while, as its loaded up when i hit the throttle from idle if I have had it just running at idle for a minute. I have performed every test in the mikuni manual ,and everything points to the low speed jet. My pop off is 15 PSI in all 3 carbs. I am really running out of things to try. Any advice for something I may have overlooked would be greatly appreciated. Oh ,and compression is good.....checked out at 115, 120, 120 last time I checked it.

    Thanks
    Bryan


  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    I highly doubt chipped corners is the issue. But if the reeds were cracked, yes.

    It sounds to me like the pop off is to blame.

    Were the needles and seats replaced?

    Did the needle tips looked deformed?

    Did you replace the seat O rings at least?

    Can you see fuel dripping from the carbs when idling?

    Did you install an aftermarket flame arrestor?

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    Needles and seats were replaced. Pop off is 15 PSI so its not too high. I have the stock flame arrestor

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    i thought pop off was supposed to be around 20-25 psi?


    Edit: my bad was thinking something else just checked manual and its supposed to be 10-18psi.

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    I think the 780's are 20-24 PSI Im leaving now to pick up my new jets and try them out. I will have a report sometime tonight.

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    Results are in. Changing the low speed jets and going one size bigger solved all my problems. No more bogging, gets out of the hole quicker and just generally ran incredibly well. it idles without loading up and acceleration is quick and smooth, no bogging or gurgling. I finally have this machine running right.

  7. #7
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Congratulations!!!!

    Make sure to check your piston wash after a bit to make sure you're getting enough fuel. Just to be safe...

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