120ST failed lifter--- but caught in time

[Spazz]

Well... it took 23k miles to get 'lucky'.. LOL!

After a noisy top end led me to an inspection, i COMPLETELY OVERLOOKED this lifter... so it went back together, adjusted the pushrods and the 'CHIRPING' started. Pulled it back apart for a better inspection and found it. TW-408-6 cams, billet cam plate, high volume oil pump are going back in... I got lucky... could have been WAY worse.

By the way... HD put a new blurb in their SE BOOK... regular inspection/replacment of tappets.

What the interpretation is from MY DEALER===== replacement every 10-15k!

 

[hulkss]

Inspect your exhaust valves seals too. Mounted directley on the valve guide they run very hot. If they leak just a little (too little to see any oil consumption or smoke), the exhaust valve stem with get coked up and stick in the guide. Listen closely to your rod bearings also.

I rebuilt my 120ST 3 times before I pulled it for good.

 

[TomA]

Guess I better check mine out here soon then. Not having any problems but I don't want to either.

 

[Mojo]

Good post Spazz! I had really noisy lifters on my last bike after a cam change. Had to have lifters replaced and it wasn't cheap letting the dealer do it!!

 

[Cornbread]

I have been contemplating a 120ST and this is sounding like I should reconsider the thought. What would you guys suggest? I want to have some umph to have a really stout running bike but not looking to “hot rod” or race anything, just kinda show my buddies up occasionally when they get cocky lol. Any advice? Thanks.


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[hulkss]

Get a new M8 114. I had to rebuild my 120ST every 10,000 miles.

 

[BillyBob]

What about the 117?


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[hulkss]

What about the 117?
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That's fine too. Just a slightly bigger cylinder bore on a 114.

 

[prodrag1320]

build your 120R to 124" using S&S flywheels & cyl/piston kit,good strong motor that will last forever,we do a lot of them here

 

[Cornbread]

Get a new M8 114. I had to rebuild my 120ST every 10,000 miles.

Thanks for the heads up Hulkss!


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[Spazz]

Dyno results are in...

120ST
58mm TB
5.3g injectors
D&D Boss Boarzilla

Before:

(259E cams)
124hp/129tq

After:

(TW408-6 cams)
126hp/133tq

It's still at the shop to tweak on the low end off the line. I picked it up and has some hesitation/ lag on the throttle tap that they are going to correct

120tq at 500 rpms less.... Im digging that alot!