The original problem seemed to be rough edges on the chains caused by dull stamping dies , along with the high pressure tensioner springs and poor shoe material in the early 88's. All these issues had been addressed years ago.

The issue I wonder about on the M8's are how are the comp's fairing ?

 

yeah, the woes of pre hydraulic yesteryear are well documented..sounds like the preventative maintenance on the M8 shoe should be treated the same as the TCs, good idea to replace around 50K since going through the trouble of inspecting is a fair amount of work. Nothing ever in the manuals about it being an inspect or replace item..heck, I dunno', maybe HD believes they are a lifetime of the bike item

as far as the compensators, that should be a different thread / post

 

But likely doing just as well. I haven't heard any real problems with them like the pre-17 comps.

 

yeah, and Lord knows we would have a 100 page thread by now if one had actually failed!

 

I've seen some posts here and else where showing hyd shoes with 80K that have some wear but not bad , I'd agree as long as your that far why not just replace them since you have it apart.

 

I tore my M8 down at 12,000 miles to do a Stage II. Tensioner shoe wear was not seen, nor could I feel any wear with my fingernail.

I pulled my twin cam down at 88,000 miles to check for wear and I found the shoes to be grooved about half way through the plastic. Of course I replaced them but I came away thinking that those shoes would have easily went 100k if I wanted to chance it. Of course when you are tore down already, to not replace them would have been foolish on my part. No question about it, the hydraulic tensioners that replaced the spring tensioners were a big step forward. And, as often is the case, I wonder to myself why it takes the MOCO years to make fundamental changes in anything. But that is another topic for a later discussion.

 

The M8 has compression relief and beefer stator for more electrical startup so less strain on the comp. My old Dyna stage 4 with new batteries was a slow cranking beast and I would hold my breath as she slowly cranks over with the SE comp working hard!. Not with the M8 she cranks fast and free.