1990 honda cr500

[jay dave]

• 
  hey there how are you? listen i need a little honda knowledge. i was reading about the 500 electrical change to the digital 250. i bought a pos 1990 cr500. as of now im a little over four grand in it. i done all the work myself except two trips to the bike shop. heres my issue. every single bearing and seal has been replaced. brand new $700 cylinder ,oem stock piston and rings. after i got the motor together i started the bike and it ran like s--t. i tinkered with it and got fed up and took it to a local bike shop. they charged me $200 for a carb rebuild and said it was fixed. got it home and it still ran like s--t. but i could adjust the air screw after it warmed up and finally the power band would kick in. so i called the shop and told them what was going on. they said to bring it back and they would find the problem at no charge. he said he pressurized the top end how hw done it i have no clue. he did tell me he was surprised cause usually when folks do their own work theres a leak somewhere in the top end, he told me i did a good job cause it held pressure with zero loss. he called me like two days later and said he was a hundred percent positive it was the stator pick up coil cause he tested the spark and it wasnt the same pattern or something of the sort. i told him to replace it. i picked it up yesterday $200 more. got it home and it ran like s--t after he said he personally rode it. i came in lol and sent him an awful message and i'm not that way but i'm really frustrated with it. i went back out and looked the bike over and the spark plug was in by just a couple threads. screwed it in and it ran perfect. so i came in and sent him a message and apologized.i had plans to go riding tomorrow so i started the bike early today and it sounded perfect. so awhile ago i loaded it and took it to a buddies house to run the heck outta of it. i started the bike and it sounded like s--t. wouldn't open up. i got it warmed up and took off and it leveled out. theres hesitation when you crack down on the throttle but it'll finally open up. so what they just did with the pick up coil didn't help it at all. can someone tell me what my issue is please!

 

[Ted Jenkins]

First of all this is a place where we often argue about Stihl Husky and Macs. For most part many will not know what you are talking about. Take your fuel tank off shake it and drain it. You may need to remove the air box to do it well. When you pour the fuel out into a clean container look for debris. If you see any water deal with it. Take your petcock off and inspect. Then take your carb off and blow out with air making sure there is no debris. Look for any torn sections in gaskets and O rings. Look at your plug to see what color it is dark brown a little rich light tan too lean. The air screw on MX bikes should mean nothing they have no purpose unless you are trying to get them to idle. Dirt bikes should not idle. About one turn out is all you need to know. The rod down the center of the carb is how the carb is tuned. Raise the rod by pulling the clip off and reposition rod higher will make a richer mixture lowering the rod will lean the mixture. If your mixture is way off you will need to increase or decrease the main jet size, The primary jet should be taken out to see if a particle is plugging the opening. The primary jet is all most never changed so no need to mess with it unless you are racing are something. Go to Flea Bay and buy a used or new CDI Box for a CR 500. All most all the years will work. The ignition coil should also be changed. The coils are all most all the same for CR 250's etc. Now do this process between running or riding so you know what makes the biggest difference. The flywheel/magneto are very simple. There are two magnets in the flywheel. One is to charge the CDI box and then the other is a exciter which tells the CDI box when to fire. The pickup coils are usually bullet proof so unless you see something out of ordinary leave it alone. Dirt bike riders always park there bikes where they can watch the neighborhood while they tear down their scooter. Good luck Thanks