Bogging off idle

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firsthere
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Re: Bogging off idle

Post by firsthere »

Have you checked the breather for signs of excess oil. Its the only other place the oil could go other than a noticeable case or seal leak.

FWIW my past leak down tests resulted in a loss of 1 PSI in 15-20 minutes.
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Re: Bogging off idle

Post by JZ05220r »

firsthere wrote: 08:13 am Nov 01 2022 Have you checked the breather for signs of excess oil. Its the only other place the oil could go other than a noticeable case or seal leak.

FWIW my past leak down tests resulted in a loss of 1 PSI in 15-20 minutes.
I have checked that. My leakdown was 2 psi lost in 8 minutes . Thanks
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Re: Bogging off idle

Post by JZ05220r »

I simply don’t have the time and space to replace the crank seals myself. I’m going to just have Ken O’Connor racing do it for me after my 91 Kdx project is done. Seems like they do really good work and less than an hour away from me.
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Re: Bogging off idle

Post by JZ05220r »

I actually did message frp a week after but shrugged it off when he said something like if the bike is on its side stand it can throw off the reading. I always balanced the bike whenever I checked.
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Re: Bogging off idle

Post by MoonStomper »

I’ve installed new seals on projects that failed before. Which is why I wouldn’t have cracked it open unnecessarily. I’m just super cautious about opening cans of worms. Seems like it usually burns my tail. Having met Jeff and gotten to see him work, I would not worry about his work or his word. Sometimes things just go wrong.
Last edited by MoonStomper on 05:24 am Nov 04 2022, edited 1 time in total.
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Re: Bogging off idle

Post by DonnyV »

Does it smoke like a lot, if it's burning oil it'll smoke, on the leak down did you spray soapy water around the reed boot area and leak down tester? I still think it's jetting, just my thoughts
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Re: Bogging off idle

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DonnyV wrote: 01:28 am Nov 04 2022 Does it smoke like a lot, if it's burning oil it'll smoke, on the leak down did you spray soapy water around the reed boot area and leak down tester? I still think it's jetting, just my thoughts
It sometimes will smoke too much and smell weird but sometimes it’s cleared out. I did check the 2 reed gaskets as I am using v force 3s. I’m trying a CEJ coming from the DEK. I wanted a DEJ but their are none available.
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Re: Bogging off idle

Post by JZ05220r »

MoonStomper wrote: 08:52 pm Nov 03 2022 I’ve installed new seals on projects that failed before. Which is why I wouldn’t have cracked it open unnecessarily. I’m just super cautious about opening cans of worms. Seems like it usually burns my tail. Having met Jeff and gotten to see him work, I would not worry about his work or his word. Sometimes things just go wrong.
Yea I doubt he did anything wrong. I think I am just unlucky here at this point. I’m still going to explore jetting for now.
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Re: Bogging off idle

Post by John_S »

Don’t explore jetting a whole lot if it’s losing any trans fluid at all. It’ll be a waste of time and frustrating. When you get around to getting the crank seals replaced, order at least a 45 and 48 pilot jet so you’re ready when your bike is fixed.
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Re: Bogging off idle

Post by MoonStomper »

I’d contact Jeff and see if he has any ideas where your trans fluid might be going. It’s probably something he’s familiar with and can help.
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Re: Bogging off idle

Post by JZ05220r »

John_S wrote: 01:22 pm Nov 06 2022 Don’t explore jetting a whole lot if it’s losing any trans fluid at all. It’ll be a waste of time and frustrating. When you get around to getting the crank seals replaced, order at least a 45 and 48 pilot jet so you’re ready when your bike is fixed.
It is dropping somewhat slowly between ride but very noticeable after 8 hours or so.
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Re: Bogging off idle

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DonnyV wrote: 01:28 am Nov 04 2022 Does it smoke like a lot, if it's burning oil it'll smoke, on the leak down did you spray soapy water around the reed boot area and leak down tester? I still think it's jetting, just my thoughts
After trying a new needle, my current jetting is 38 pilot, #7 slide, CEJ needle and 150 main. The CEJ actually seemed to wake it up a bit up to about quarter throttle. I believe with the porting their was a reduction in low rpm/ low throttle position vacuum. I’m thinking the porting may have sacrificed some low rpm vacuum. If their is less vacuum at 0-1/4 throttle, technically you would need to increase the jet size in that throttle range. Apparently porting can sometimes act like a camshaft where you sacrifice low rpm vacuum for high rpm vacuum or vice versa. Increasing engine vacuum will increase the engines ability to draw fuel through the carb on a given size jet so you would have to switch to a smaller size jet to balance that out. Logically it’s the other way around when decreasing vacuum. I chose to lower the needle diameter a step compared to the CEK as the needle diameter effect lower throttle positions. Maybe I am overcomplicating this but seems like an improvement. I am losing trans oil at a slow rate
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Re: Bogging off idle

Post by bufftester »

If you're losing your engine oil all the jetting in the world isn't going to help. You need to find and fix the leak first.
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Re: Bogging off idle

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bufftester wrote: 09:07 pm Nov 08 2022 If you're losing your engine oil all the jetting in the world isn't going to help. You need to find and fix the leak first.
Yea your right. I can’t seem to get it right no matter how much changes I have made. It’s still very quick but just not as smooth as it should be. The engine runs decent for the first like 10 minutes, feel nice and snappy, but eventually the idle starts getting all wierd, dropping then hanging. I start getting hesitations upon upshifts. Doesn’t even feel good in neutral when I blip the throttle compared to when it’s still warming up where it feels crisp and returns pretty nicely.
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Re: Bogging off idle

Post by JZ05220r »

Can a bad right side crank seal allow air through like the left side cranks seal?
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Re: Bogging off idle

Post by JZ05220r »

JZ05220r wrote: 05:28 pm Nov 09 2022
bufftester wrote: 09:07 pm Nov 08 2022 If you're losing your engine oil all the jetting in the world isn't going to help. You need to find and fix the leak first.
Yea your right. I can’t seem to get it right no matter how much changes I have made. It’s still very quick but just not as smooth as it should be. The engine runs decent for the first like 10 minutes, feel nice and snappy, but eventually the idle starts getting all wierd, dropping then hanging. I start getting hesitations sometimes after upshifts. Doesn’t even feel good in neutral when I blip the throttle compared to when it’s still warming up where it feels crisp and returns pretty nicely.
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Re: Bogging off idle

Post by SS109 »

JZ05220r wrote: 05:46 pm Nov 09 2022 Can a bad right side crank seal allow air through like the left side cranks seal?
Yes, it can. However, it will mainly pull in trans oil.
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Re: Bogging off idle

Post by bufftester »

I would guess since you are losing oil that your crank seals are in need of replacement
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Re: Bogging off idle

Post by JZ05220r »

bufftester wrote: 03:48 pm Nov 10 2022 I would guess since you are losing oil that your crank seals are in need of replacement
Yea I have it just above the sight glass now. Gonna ride it a bit more to be sure. I’ll know when the level drops below the top of the sight glass. Thanks
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