1988 Sporty Knock/Ping (videos inside)

[JBarrettB]

My guess is that you have a failing roller on one of the tappets. Be sure and check the cam for damage too.

JB

[FLTRI]

Alright so I checked the exhaust as well, all was tight with no apparent issues...

How did you check for cracks in the exhaust pipes?

Wrapping exhaust pipes is great for keeping all the HP's in there but will make the pipes brittle after a while and will stress-crack.

Typically a crack is closed when the pipe is cool then opens up...more as the engine gets hotter.
Just a thought...
Bob

[Panzer]

Well 88, how did it go?
I'm sure I'm not the only one looking to see how you made out.
                                     

              450 views............we're waiting!!

[88sporty]

Alright sorry for the long time between updates, I really just haven't had much time to work on her. So, I tried to get the lifters out without removing the blocks, no go. I was probably doing something wrong but no big deal, I'm actually kind of glad I did it because it led me to finding out a few things that need fixing. First off, I had a pretty serious leak at the gasket between the head and cylinder on the rear jug so it was running noticeably hotter in there. Second was I noticed how small the bore and pistons looked, I had always been told that the piston on a 1200 shouldn't be able to fit in between the studs for the cylinder and low and behold they did. Measured them out to 3", so it would appear I got straight had by the PO telling me it had a 1200 kit. Not all bad considering the crosshatch on my 883 jugs was looking pretty worn so a 1250 kit it is. I think I'm going with NRHS, unless there is someone else out there with better quality and a good price point, what do you guys think?

Next I was finally able to get the lifter blocks off and get those old lifters out of there. I swear everything in this engine, gaskets included, was OEM so it really is a good thing I pulled it all apart. Unfortunately Debrix cycles sent me the incorrect lifters so I was not able to install those, but I took a look at my cams and all looked well, no uneven wear on any of them, nothing appeared to be chipped or broken. I then looked over the bottom of my pushrods and noticed some uneven wear on the rear jug exhaust pushrod, so I think the lifter diagnosis is correct, at the very least. While all of the others looked nice and smooth and shiny this one was slightly scratched up and nicked all around the center hole. So once Debrix makes good on this lifter exchange and I get my kit from NHRS I should be golden. I've got a buddy of mine sand blasting the heads so I can repaint the faded cracked paint job that was on them and I also finally had the space to fix an oil leak that has been plaguing me. So all in all it was kind of a good thing I tore her apart, looks like I'll be getting a decent amount more power out of her with the 1250 kit and I'll be able to put some nice gaskets in there to stop the leak to the rear jug that was probably robbing me of some power.

Now someone above me asked about an exhaust leak. It turns out I was wrong about that too. I guess I somehow missed that one of the flange bolts on the forward head was backed off pretty good but it was just such a tight space I must have mistook it for being properly tight. I noticed this when I took the exhaust off of the head to give them to my buddy for sand blasting. I've got some new hardware for mounting it that should make it a fair bit easier to torque down instead of the rusted crap that was holding it in place. Now I haven't taken the heat wrap off to check for actual cracks to the pipes themselves, should I? The wrap looks like garbage anyway but having it kind of frayed actually goes with the flow of the bike, sad as that sounds, haha. I guess I'll take it off and rewrap them so I can check for leaks, you said that the cracks show up when warm, but wouldn't it be the opposite? I'd figure they'd be more prevalent when cold because the metal contracts thus exposing more of the crack, either way, if I can't see any cracks when they're cold I thrown them on and get the bike to operating temp and check again just to be sure.

Honestly thanks for all of the help here guys, without the stuff you've posted up this would have been a horse of another color and I'd without a doubt be in over my head.

[PC_Hater]

NRHS know what they are doing.
Do what they say and all will be well.

[88sporty]

Thanks for the tip, I don't think I've heard a bad thing about them yet so I'll be OK with the slight markup over a lot of the other kits.