EVO 80 Top End and Bottom End

Discussion in 'General Harley Davidson Topic' started by wdrworm, Sep 9, 2013.

  1. wdrworm

    wdrworm New Member

    carb kit. Performance was good, but after a few months was told that I was having severe "blow-by". Symptoms was oil coming out of the carb and breather. Top end job was done with Wiseco 10:1 pistons and bored one over. I started the break in process by riding it for 500 miles at varying speeds. While I was breaking it in, I noticed that the power was not where I thought it should be. It didnt "feel right" or "sound right" and I thought the vibrations were alot more that they should have been. After the 500 mile, I started to ride it a bit harder and it seemed that the motor was being "held down". I took it back to the shop (independent shop) so he could drain the fluids and cut the oil filter in half to see if there were any metal shavings. I asked him to ride it before he did anything. He was gone for about 20 minutes and came back and said that he thinks there is a problem with the crank/fly wheel and that he feels that something is holding the engine back. Now he wants to do a bottom end job.
    My questions are:
    1. Does this sound legit? The bike had an easy 65K ridden on it and I thought that this was too soon for a total rebuild.
    2. Did I hurt the top end by riding it for 500 miles with a "suspect" flywheel/crankshaft?
    3. Am I throwing good money away? I dont know what else the problem could be.

    Any help or insight would be greatly appreciated.
    Thanks - Worm
  2. HDDon

    HDDon Experienced Member Contributor Retired Moderators

    First how many miles are on the bike? Are you running stock cams and stock pushrods? What do you mean by carb kit? Why did you go to 10:1 compression pistons? Did your indi do a compression check and a leak down test? Oil coming out of the carb and breather could just be the umbrella valves needed to be replaced. What AC are you using?
  3. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    If bike was running ok prior to top end being done i would suspect something not right with the top end job
    Compression test, leak down test, should be the start point not just a quick ride and some expensive work needs done

  4. wdrworm

    wdrworm New Member

    65K miles on bike. It has stock cams and pushrods. Carb kit is a S and S Super E carb. After the EFI failed for the 4th time, we had the EFI removed. As far as the 10:1 pistons, I got a good deal on them. He told me the blowback was caused by something called "piston slap". Not sure what you mean about AC.
    Thanks for your help!
  5. Jennmarr

    Jennmarr Junior Member

    Is this the same shop that did the machine work to install your new pistons?
  6. Jack Klarich

    Jack Klarich Expert Member

    Rare an Evo bottom end needs service with that kind of mileage, I would have a look at the oil pump and breather gear, too much oil in the bottom end will cause a lot of drag on the flywheels:s