Topic: HELP!!!! IDLE ISSUE

[ok333]

found my problem this weekend.  Don't know why the pushrod got smashed, I'm guessing the clutch springs are too stiff. If anyone has an idea please share it. I bought stock clutch springs to put in it and will probably just make a new pushrod.


also picked up two cb750's last weekend they are both in rough shape and the motors are locked up. also the owner said he had a title, but it was just an application for certificate of title, so ill have to go back to get a bill of sale. One of them i've taken apart I will probably part it out since there is no title and there is not enough there for me to build it.

[ok333]

got the clutch fixed didn't see anything that could have caused the pin to get crushed. I went ahead and went back to stock clutch springs anyways. Also put silicone around my carb manifolds. When its idling I get this weird puff or pop, sounds like a backfire. I figured it was a vacuum leak but I've synched the carbs and have sprayed starter fluid around the carbs and there's no change in idle. I also checked the valve adjustment and its perfect. so I'm not really sure the problem there. Also went down to 105 main jets and it seems to like it better, next week ill throw the wide band on and check the AFR.

also scored this on one of the 750s I picked up


got a cheap clutch cover on ebay that matches the horizontal fins.

[Stev-o]

Also put silicone around my carb manifolds.

Prolly needs the o rings replaced to do a proper fix

[ok333]

it has new O-rings in it, and new carb insulators. The only thing I can think of is maybe the crush washers on the exhaust.

[calj737]

...or, the fuel level is too low and you're running lean at idle. 

[ok333]

That could be it. I've done the clear fuel line test a few times before and it seemed like it ended up being different each time, these carbs are finicky. It was set correctly the last time I checked, but I'll check again.

[ok333]

went out for a ride with my dad this weekend, and was able to race him on his Harley a couple times. Once we started heading back home I stopped the bike at a stop sign and it died and lost power. I pulled it over and checked the fuses and in doing so it smelled like paint was burning and then I looked over and my battery was smoking and started to expand, then the lid popped off the top of the battery. Long story short looks like I just fried a $150 battery . I don't know what caused it; best guess is there was a plug on the rectifier that seemed a little loose, if it wasn't that then my rectifier may be acting up, which is weird because I bought it new a month ago. I have a voltage gauge on the bike, but its cheap and it started giving me weird readings halfway through the ride even though everything appeared to be charging fine. When I came up to the stop sign the gauge was flickering and showed 10 volts and then dropped to 6 before I stopped, but I thought the gauge was messed up, so I wasn't worried about it. Now I'm planning on getting a bigger gel battery and placing it under the seat, since I like riding the bike far distances and the battery I had only lasted about 15 minutes on a charge. So having more time to tell if somethings wrong and having a more forgiving battery would be nice. I knew when getting the battery that LiPo's are worse when it comes to over discharging and overcharging but I took the risk, I'm just glad the bike died before the battery caught on fire.

[calj737]

Doubt its the rectifier, and probably the regulator side of your component that failed. It also sounds as though your battery wasn't getting a proper charge.

Before you buy another battery, you would do well to use a donor battery that's in a known-good condition, fully charged. Then fully test the charging system and electrical connections. Fix what needs repair. Then replace your battery with another new one.

[ok333]

      Ill test the charging system with another battery I have laying around. I believe the charging system works fine because it was charging at 14.4v once I was over 3k rpm during my ride, but I don't know what it was doing when my gauge was acting up. I'm going to order a better gauge and I was looking at battery discharge protectors ( I can post a link to one if the forum allows you to). The battery discharge protectors turn off power going out of your battery once your battery drops below a specified point and it will also stop charging your battery once it goes over a specified point.
      I'm wondering if my rectifier/regulator possibly fried a connection in the battery (from over charging) and that's what caused the battery to stop charging. I have seen on my voltage gauge the charging system put out 14.6v before when I was at high rpm's, and it may have put out even more since I was at about 10,500rpm.
      Also the battery could have not been getting a charge due to a loose connection. When I pulled over I was checking wires going into my reg/rectifier and I pulled one of the wires and it came right out, the wires are hidden under the tank so I couldn't tell if it was even plugged in, in the first place, but that could have been my problem. I guess the only way to tell is connect another battery and check the charging levels.

[calj737]

      Ill test the charging system with another battery I have laying around. I believe the charging system works fine because it was charging at 14.4v once I was over 3k rpm during my ride, but I don't know what it was doing when my gauge was acting up. I'm going to order a better gauge and I was looking at battery discharge protectors ( I can post a link to one if the forum allows you to). The battery discharge protectors turn off power going out of your battery once your battery drops below a specified point and it will also stop charging your battery once it goes over a specified point.
      I'm wondering if my rectifier/regulator possibly fried a connection in the battery (from over charging) and that's what caused the battery to stop charging. I have seen on my voltage gauge the charging system put out 14.6v before when I was at high rpm's, and it may have put out even more since I was at about 10,500rpm.
      Also the battery could have not been getting a charge due to a loose connection. When I pulled over I was checking wires going into my reg/rectifier and I pulled one of the wires and it came right out, the wires are hidden under the tank so I couldn't tell if it was even plugged in, in the first place, but that could have been my problem. I guess the only way to tell is connect another battery and check the charging levels.

Sounds like you have some work to do. I would not waste time or money on a "discharge" protector and instead have a sound charging and electrical system and just take care of your bike.

[ok333]

Before the last ride I checked the float levels in the carb with the clear line test. The levels were all about an 1/8th in below the carb body. So I'm guessing I still have a vacuum leak. On the last ride I tried to turn the idle up and it then wouldn't idle back down once I came to a stop so there is definitely a vacuum leak somewhere. Since I have ruled out it coming from the valve adjustment and intake boots, my best guess is the carb slide may be worn. I have two sets of carbs and the bike did the same thing with the other set on, so it would be weird if two sets were worn. I'll try running the bike and using propane around the carb body to see if I see a difference. I might even take the top caps off the carbs and see if I can hear any blow by through the slide. I have also checked spark and timing, but if I don't find a vacuum leak I'll start checking the timing of each plug wire.

[ok333]

and I think I figured out my battery issue. The night before I turned the key to off instead of lock like I usually do, and when I went to start the bike the voltage gauge didn't even light up. After taking a look my cheap Emgo ignition switch, will sometimes not be completely off when on the off position, and my headlight drained the battery. I tried putting the battery on the charger and it wouldn't go above 8 volts even after 24 hours of charging. So I ended up jumping the bike and riding it. My guess is the battery was already bad and didn't want to charge after being drained. During the ride the battery got to 13 volts once but stayed at 11.6 volts most the time before my gauge stopped working.

[calj737]

An over-discharged lithium battery is most likely not going to recover. Their Achilles’ tendon I’m afraid.

[SOHC4 Cafe Racer Fan]

Yes.  Unfortunately, once they fall below a certain voltage threshold, they are DONE.

I've had two go that route.

[ok333]

I ordered a gel battery this time. I really liked the lithium, they put out a lot for their size and have a lot of cold cranking amperage too. But I can get a gel battery that has a little more cranking amps and has twice the amp hours for $50 and it's only an inch bigger each dimension. Hopefully I can still fit it under the hump, but I've been wanting to make some side panels for a while now so it could be an excuse to do it.

[SOHC4 Cafe Racer Fan]

Here's a brief breakdown on the differences between AGM and gel batteries.  You may want to re-think and do an AGM.

https://www.throttlexbatteries.com/details.aspx?p=A4D3D61DCEB3C859&ppid=59924&beid=4C71C77B4CB63E74

[ok333]

I looked at the AGM's and none of them said what the CCA was. and the gel ended up being smaller and lighter. If I go with another battery in the future I would like to try the AGM after reading the article you posted. there was a lot of good information there, especially when talking about the output and temperature of use. I looked around a little more and the AGM also looks to have better charging characteristics, and they're cheaper.

[ok333]

Finally fixed all of my tuning problems. I figured the only thing left was bumping up the pilot jet so I bought some bits to drill them out, but the bits are so small that they snapped as soon as they started to cut. So I just ordered some new 45 pilot jets and installed them and all of my tuning issues went away, but now its too cold to ride.

...and ill have to fix all of my old photo bucket links again, for some reason the forum didn't save anything I posted last time I was on.

[Stev-o]

Finally fixed all of my tuning problems.

...and ill have to fix all of my old photo bucket links again, for some reason the forum didn't save anything I posted last time I was on.

Congrats getting it tuned correctly.   

Fotofucit does not provide free third party hosting of pix, you'd have to pay $400/year to continue to use them....outrageous!

Many of us have switched to Flickr or you can just attach, your choice. 

[ok333]

Thanks!
 and yeah I switched to picasa web, and I had switched all of my old photos over and made a few posts; but I just checked my thread yesterday and all the changes I have made, and posts I have made over the last month have been deleted for some reason.

[Stev-o]

...and all the changes I have made, and posts I have made over the last month have been deleted for some reason.

This website crashed late last month and about 10 days worth of posts were lost.   

[ok333]

That explains it, thanks!
I spent about 2 hours changing all of my old photos over and then lost it, so I was pretty bummed. but ill try to fix them one day this week, and here's some pictures that got lost of the new battery box.

[ok333]

I've been working out the bugs on the bike and have come pretty far on it. I made a new wiring harness for the bike so now I don't have any electrical problems. I also put a rust free tank on the bike so that I don't have to worry about the carbs clogging. For some reason I still have a hanging idle. if I rev the bike the idle hangs at 3000 rpm and takes a long time before it drops. It used to hang at 5000 rpm but I changed all the brass in the carb to factory brass and changed the needle position to the second groove.

- My carbs are PD46C, The head was done by MRieck and is ported with oversized intake valves. Bike runs really good I've been messing with the tune for 6 months now and have everything where I want it but cant get rid of this sticking idle.
Here is everything I have checked and done to try and fix the sticking idle.
- clean carbs (like 7 times)
- replace aftermarket brass with factory
- replace rubber intake boots (twice)
- spray around carbs for leak, idle didn't change
- check valve adjustment (looked great the 5 times I checked)
- vacuum sinc carbs after each install
- check to make sure fuel filter isn't disrupting fuel flow, even took it off and still had problem
- check gas cap to make sure its venting, bike still does it with cap off
- checked float height and adjusted fuel height to be 2mm below bottom of carb body. this was done with the clear fuel line method. I also had them set to 12.5mm and 14.5mm but noticed it was inconsistent so dialed them in with clear fuel line.
- check to make sure slides aren't worn. I am on my second pair of carbs because the first set had wear on the slides
- checked carb vents
- checked throttle cables
- checked manifold o-ring and replaced several times
- changed to the next size pilot jet, bike is sluggish now and still have the problem.
- oh and I've checked the idle thumb screw and pilot screw

If you can think of anything else to check please let me know, because I cant think of anything else it could be.
I can post a video of my issue if that would help.

[Medyo Bastos]

You’ve got a mechanical issue, check your spring; check and lube your throttle cables


Sent from my iPhone using Tapatalk

[ok333]

the throttle cables are new and I've lubed them. Also I've put an extra spring on and it still did the same thing.