Originally Posted by Hoyt 1911A1

I am wondering if the move to the new hydraulic tensioners necessited the oil pump upgrade? Way back when I got the updated tensioners they came in a kit with the new oil pump.

I must admit I also liked the idea of the billet came plate vs. cast.

Originally Posted by hattitude

Short answer:

The earlier Twin Cams (88" engines) had spring cam chain tensioners that could fail, causing serious $$$$$ repairs.

It was considered good preventative maintenance to replace the Cam Chain tensioners between 20K & 30K miles.

I have recently found some low mileage 88" Twin Cam engines that had severely pitted cam tensioner pads. I suspect it is due to age, instead of mileage. IMHO, I would not buy a Twin Cam 88" bike, without inspecting/upgrading the spring cam tensioners almost ASAP, regardless of mileage.

It is a simple upgrade, with several different upgrade options, just labor intensive. It's more involved than just a basic service, but not really all that hard to do. There was a simple and low cost upgrade of new tensioner pads($$), up to removing the cam tensioners altogether and going to gear drive cams ($$$$$).


The long answer:

The spring loaded cam tensioner pads wearing quickly, then breaking apart was an issue. The link chains used on the cam gears on the front and back of the cam plate were also considered part of the quick wear issues with the tensioner pads.

The other issue was the B148 size inner cam bearing by INA, were caged bearings and there were a higher than acceptable failure rate on these. That would cause serious $$$$ repairs like if the cam tensioner pads were to break apart. The fix was to replace them with the then Torrington brand captive needle bearings. The current replacement captive needle bearings are now made by Koyo.

While HD still used the INA brand inner cam bearings in newer Twin Cam (and some M8) engines, they were switched during the cam bearing update to B-168 size. There were far fewer failures of the size B-168 inner cam bearing than the earlier B-148 inner cam bearings, but people still swap out the caged bearings (OEM INA Brand) with the captive needle bearings (Toyo brand) when going into the cam chest for any reason.

All of the cam chest issues of the early Twin Cams were fixed with all '07+ models. HD went to a different cam plate and oil pump, with roller chains and hydraulic cam tensioners for the 96" engines. The newer cam plate components can be retrofitted to the older Twin Cams if you switch to conversion cams (the cam plate bearings & inner engine case bearing sizes changed).

The 2000 Twin Cam 88" had some good points too.
The big one was hot forged cranks, and a left side timken bearing on the crank. These gave the engine very strong bottom ends that rarely had runout issues, and could handle power improvements with ease. (unlike some of the '05 and later Twin Cams).
It had the old-style compensator, like used on EVO engines and Shovelheads, that was virtually bullet proof. (unlike the '07+ Twin Cams with the "improved" compensator).
It also has the manual primary chain adjuster, that avoided the issues with the self-adjusting primary chain adjuster used in '07+ models. It was problematic until an upgrade in 2014.


Believe it or not, that long version is still a short story about the issues and fixes for early twin cam engines, but it's probably more info than you wanted...

However..... You did ask...

Originally Posted by K9Been

I put in an S&S 510g with 4 gears. Of course you will have to check crankshaft run out to insure you can use the gear kit.

Originally Posted by hattitude

While I wasn't privy to the design and engineering of the '07+ cam plate, it would make sense that they improved the flow a bit to ensure proper function of the new hydraulic tensioners.

Additionally, they did include the newer, higher flow oil pump with that SE cam plate kit. The way they marketed that new oil pump, it's no wonder many thought the old pump was inadequate.

This is from the description on the SE cam plate upgrade:

• The kit includes an improved Screamin' EagleŽ High-Flow Oil Pump that provides increased oil pressure at high-operating temperatures
  
• This kit increases the oil supply by 23% and scavenging by 50% when compared to the '99-'05 Original Equipment oil pump, and reduces operating temperature of bearings to improve bearing life
  

In any case, better oil flow isn't a bad thing. However, the 88" cam plate with spring tensioners, that had the tensioner pads switched to the better CYCO pads, worked just fine with that OEM pump.


FWIW....
I addressed my spring tensioners by going with an '07+ cam plate and conversion cams so I could switch to the roller chains like the '07+ bikes used. I didn't like that the SE version still needed the link chain between the cams behind the plate. The '00-'01 Twin Cams using the SE upgrade, that used cam position sensor, needed to keep the OEM front sprockets and link chain. Since the link chains were considered an accomplice to the fast spring tensioner pad wear, I always thought the SE cam plate upgrade was only a partial solution..

Then of course the oil pump envy set in, and I used an S&S '07+ cam plate & oil pump for my solution...

Originally Posted by Scootertrash60

Thanks for all the technical info!!

So realistically, depending on my runout, I could just go with cams, cam plate and use the stock oil pump? I'm also going to upgrade the lifters ( I have one that seems to bleed down after the bike sits, clacking on start-up momentarily) and push rods.

I don't plan on any big bore stuff, my 85 Low Rider will be my hot rod

Originally Posted by Max Headflow

. I like the DTT. Replace the inner cam bearings for sure.