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Twin cams

Post Mon Mar 26, 2007 2:30 pm

Posts: 1676
Location: Interlaken, NY USA

immotors, Now you tell me :lol: I just bolted the cases closed over the weekend, and it's now in the frame. I ended up soldering closed my first holes and redrilling them progressively larger until I got to #64 rear, #65 front. I needed different sized holes to get equivilent jets, probably due to quirks in the flow of my oil passages. I am plumbing the oil filter in the supply line, just before it goes to bottom end and piston jets. I"m using a aftermarket knockoff of the original canister filter. The jets are very susceptable to plugging by small particles.
Stay tuned, we'll see how it does.
Dr. Dick

Post Mon Jan 21, 2008 12:57 am

Posts: 1538
This tidbit is for tc88 owners to watch out for, or those considering getting one...
You can have 'em.... EVO is new as I go...

And you thought all TC88 cam bad-stuff was history.

It started out on a country road on a sunny Saturday afternoon. Had
I heard a noise? Perhaps a little more cam chain than usual? My '02 Road
King had over 37,000 miles and a stout set of Vance and Hines pipes. Little
noises had come and gone over the last few years, usually traced to loose
heat shields, junk rattling in the saddlebags, or collateral damage from the
time my brother-in-law was late stopping for a light and used the left
saddlebag as a launch ramp.

Our ride took us through Texas, so I stopped in to ask
Ken XXXXX, the service manager at American XXXXX HD about it. Their shop
had been the only ones to figure out that my chronic primary leak was
actually the result of an undersized starter jackshaft. Another shop had
replaced the inner primary and resealed the works four times without
success. American XXXXX had also done a crackerjack job of fixing the
aforementioned launch ramp damage.

Ken told me the sad tale of the cam chain tensioner shoes. These
little guys live between the cam chain and a hefty spring assembly, making
sure that the chain stays nice and tight at all RPM. This arrangement
ensures that they spend their life with their little plastic faces mashed
against the moving chain. Wow, talk about nose to the grindstone -- these
guys are dedicated. At about 1/16" inch of wear, or about 20-25,000 miles,
the plastic can start coming off in chunks.

The next stop for the plastic particles is the oil pump. If they are
small enough, they pass harmlessly through the pump, and are then picked up
by the oil filter. If they are large enough, they force the gears of the oil
pump to perform unnatural acts, resulting in metal and plastic debris in
large quantities.

When I got the '02 Road King, I thought all the twin cam bearing
stuff had been taken care of with the '99 and '00 models. The improved
assemblies, the fix kits, the service bulletins, the extension of warranties
to affected bikes and the failed class-action lawsuits had all run their
course. What's the deal here??????????

"I plan to change mine out between 20-25,000 miles," said Ken.
"If you catch them early, they are easy to fix. If they kill your oil pump,
things can go bad in a hurry."

Lots to think about as I headed home. We were getting ready to do a
22-state, 6,800-mile trip next week. Do I dare tear down the bike a week
ahead of this trip? Did I really hear anything at all? Did I dare not fix
A Gutted Road King.

These thoughts filled my head as the August afternoon heated up. The
pack finally pulled into a restaurant near my house to have lunch and split
up. I forgot about it over stories and good food, then headed home.

As I rode the remaining mile to my house, something was noticeably
different. That little whisper of a noise was a distinct sound. I cut the
motor and coasted down my street, trying to see if the noise was brakes or a
wheel bearing. No such luck, it stopped with the motor.

I restarted it as I pulled into the alley. By the time I got to my
house, it was a clear whine that rose and fell with the engine. Not a good sound.

I decided to see if there was plastic in the oil, so I cleaned my
oil drain pan with mineral spirits, wiped it dry, and drained the oil. After
I poured the oil into the five-gallon bucket I use to recycle, I checked the
drain pan. Sure enough, plastic and sparking little metal shavings were
present. I got out a magnet. About half the shavings moved with the magnet,
the rest stayed put. This meant both steel and aluminum were involved, not a
good sign at all.
Arrow points to tensioner face--when these wear out the
plastic goes into your oil pump.

Next I pulled the oil filter and used a chisel and tin snips to cut
it apart. I cut the element free of the plastic housing, and stretched out
the folds of the filter media. Sure enough, plastic and metal were embedded
in every fold.

I replaced the filter, put in oil just in case somebody at the
dealer started the bike to move it, and pushed it onto a trailer. Monday, it
was at American XXXXX HD.

Now the fun started. The bike was a few days short of three years
old and had over 37,000 miles. It did not have an extended warranty. I was
the second owner, but had paid the fee to inspect the bike and transfer the
original warranty into my name. If Harley did not stand behind the repair,
this was going to be a $1200 hit. If they did stand behind it, the cost
would be a $100 administration fee.

While the shop, full of bikes getting serviced for Sturgis, found
time to tear the bike apart, Ken went to work with HD Customer Service. It
was a tough sell. Harley handles these situations on a case-by-case basis.

While we were making last-minute preparations for our trip, I drove
out to American XXXXX. There was my bike, eight feet of assorted Harley
parts lining a lift. The tank and rocker covers were off, the cam chest was
open, and the ruined oil pump was out for inspection. The evil tensioner
shoes were worn to the point that the plastic had stripped off in chunks.

By the end of the week, the bike was back together. A new cam plate,
chains, shoes, and oil pump were getting to know each other. No metal or
plastic were found in the rocker boxes, so it appeared that the oil filter
had successfully given its life for the engine. Harley covered the repair,
so I was only out the $100 administration fee.

We made our trip, 6,800 miles through the 22 states west of Big
Muddy. I was listening to every little noise along mountain roads, down the
coast of California, and across the desert, but it made it all the way.

So what does this mean for you and your twin-cam? If you ride 1,200
miles a year doing toy runs, I'd say turn the page and forget about it. If
you have over 25,000 miles on your bike, my recent experience would suggest
that you get the tensioner shoes checked or replaced. Don't forget the chain(s)

Contrary to a lot of the stuff you read, all of the twin-cam
problems have NOT been solved, and Harley is still handling the tensioner
failures on a case-by-case basis.
The good news is that it appears to be a
fixable problem, and so far, the factory has been standing behind the

In addition you can generally buy a twinkee cheeper than a decent EVO. Wonder why ?

Post Mon Jan 21, 2008 6:59 am
Pa Site Admin

Posts: 5843
Location: Ohio USA

Very informative read Bro ! Thanks !! I'll pass that along. Pa

Post Mon Jan 21, 2008 8:24 am

Posts: 1676
Location: Interlaken, NY USA

And that's why you put the filter after the pump and before the engine. Clean oil in the tank is nice, but no crap in the rollers is better! Thanks for the info Sleeper.
By the way, the latest sporty pump adaptation is using the stock BTSV return pump mounting studs. Well, longer than stock, but same locations. No relocating holes in engine cases. Also includes more changes in plumbing oil to and from the pump. I'm pleased so far, last year did not burn any pistons, and dropped the habit of 30 years of rolling off of the throttle when running hard. Oil consumption is the next target. The engine needed a rebore, and worn valve guides are getting replaced with guides turned down to accept shovel guide seals. Intakes were sucking up oil around guides. The pump runs 60psi cold, 16 hot, with full flow to a 3 hole crankpin, plus the piston oilers. Also, found that oil pressure readings are similar with either straight 50 or 20-50. Likewise leakage, so I'm a convert to multiweight at last. She's a work in progress, for sure.
Dr Dick

Post Thu Jan 24, 2008 1:18 am

Posts: 1538
ok Pa....

Dr Dick- "And that's why you put the filter after the pump and before the engine. Clean oil in the tank is nice, but no crap in the rollers is better!"
Yes Exactly.. I wondered about this back in 1998, (when I first got the HD tc88 training manuals, for employees only).. before the '99 tc88 rubbermount bikes were released.
It became clear quickly after that, along with problems with cam bolts, etc, etc.

Dr- It sounds like thru your experiments you are zeroing in on the 'fountain of youth' for SV's. Very interesting.. Thanks for sharing your research & results.. Sounds like this is how moco should have made 'em originally..
Very impressive oil pressure !!!!

It's true: be-it motors or sex, too much friction, it ain't gonna last long.. :lol:

Post Thu Jan 24, 2008 8:39 am

Posts: 1676
Location: Interlaken, NY USA

You got that right Sleeper! And thanks for the info last year about piston oilers, you set the ball rolling. Likewise about the oil filter, you da man...
Dr Dick

Post Fri Apr 25, 2008 11:55 pm

Posts: 1538
Dr. - Well I try to add my 2 cents when I gets da chance...
Been busy hammering out a master-blaster for this year..

So new applications x old bikes = Happy days :idea: That'll work

Post Sun Aug 17, 2008 12:37 am

Posts: 1538
Little tid-bit....

HD 2009 Rear cylinder "Shut-Off mode"

HD has come out with a rear cylinder "Shut-Off Mode" for the 2009 bikes, & retro-fit kits for '08 bikes, every time you shut the throttle while cruising the rear cylinder shuts off in an effort to try reduce HEAT, to help rider be more comfortable.. WTF ???

A guy rented an '09 Street Glide & was in a parking lot w/it idling, & he was fiddling with the throttle & it went into 'rear cyl shut off mode', He said it then sounded like HD's 1 cylinder Buell-Blast.. :shock:

I know that it has gotten tougher to meet the latest EPA Tier II emission standards, but is this the best moco could do ??

S&S & other motor co.'s are meeting latest EPA Tier II standards......I personally haven't heard or read anything about them being like a "Blast Furnace" on wheels...

Post Sun Sep 07, 2008 10:17 pm

Posts: 646
Location: Detroit
Billy, over the years they have always come up with stupid ideas here and there. Remember the oblong points cam used in glides from 1970-1972--the one you had to guess where the high spot was?
New Knuckleheads? Thank, you, Jesus!!

Post Sun Sep 07, 2008 11:19 pm

Posts: 1538

UR right, many ideas don't always fly....

But they still get sent up the flagpole & see if any one salutes.. :lol:

I think HD will eventually have all liquid cooled bikes.. Currently for '08 & likely '09 they are running almost 15:1 AFR :shock:

Glad I still play with old bikes.. :wink:

Post Sat Jan 17, 2009 11:11 am

Posts: 767
Location: Pa. , USA
Read this thread with intrest as i recently purchased a used 2000 TC (carb. mod.) ST standard with 17,000 on it, haven't ridden enough to experience the heat problem ( mid winter here) so my question; is the bad breathing heads causing the TC to run hotter ? As for the cam chain/shoe wear i hear the conversion to gear driven cams is a permanent fix if one wants to spend the extra bucks, anybody done this ? like to hear your comments, thanks, Tim

PS, the only thing un-Harley about the bike so far is the counter balanced motor is almost TOO SMOOTH :?
Vintage roadracing, Class C, AHRMA # 335

Post Sun Jan 18, 2009 11:14 am

Posts: 543
Location: Wa, USA
The adjusters went out on my 05 E glide at 63,000 miles. I put in gear drive cams and am very happy with the result. The repair requires several stock parts such as support plate, oil pump, lifters and more. HD will try to sell you all the needed items individually. There is a kit, P/N 24984-99 for EFI and 24985-99 for carburated that has everything needed for the repair. You won't need some of the parts (stock cams, chains, adjusters, etc.) but it is cheaper to buy the kit and discard what you don't use. HD will not tell you about this kit, and may pretent that they don't know anything about it. You also don't need to remove the rocker covers. Just cut your pushrods with a bolt cutter and replace them with adjustable ones.

Post Sun Jan 18, 2009 2:17 pm

Posts: 767
Location: Pa. , USA
Thanks Woody, i hope to do the gear drive converson before the any damage occurs, did you use the complete S+S kit with cams or i see Andrews also has cams to work with the S+S gear kit ? Tim
Vintage roadracing, Class C, AHRMA # 335

Post Mon Jan 19, 2009 1:01 am

Posts: 1538
Tim 435 wrote:
Read this thread with intrest as i recently purchased a used 2000 TC (carb. mod.) ST standard with 17,000 on it, haven't ridden enough to experience the heat problem ( mid winter here) so my question; is the bad breathing heads causing the TC to run hotter ?


The TC88 B motor is not meant to rev high or long as damage can occur to the counter balancer stuff..

1st you have an EPA compliant carb/pipes & air filter running a LEAN AFR (least stock it was). Jetting it up (all circuits) is helpful, & heading in the right direction.

For some that is good enuff..But still will be HOT riding slow in summer & at stop light/toy runs, etc... Better cams will help some here too..

But, If you want to make it run cooler yet (as it should) & have much better performance, the Exhaust ports are too small..This is a bottle-neck for captured heat. The built-in anti-reversion dam is good but EX port needs enlarged.

Ex ports & Ex valves are also smaller than 80" Evos.

These are some of the first things many seek to have addressed to improve the temps & performance...(good Head work)

Adding gear drive is a good set-up. Some may complain it is a lil noiser than chains. But not all, & the trade-off IMO is worth it.

If you add "Gear drive cams" you will need ajustable push rods anyhow. Smaller cam base circles.

PS: running good Synthetic Oil is helpful too. Just IMO not HD's Syn 3, it's NOT truly full synthetic.
Check any independant UOA's on it.. You will see.

Amsoil, Mobil 1 etc...

My .035 (inflation)

Post Mon Jan 19, 2009 9:02 am

Posts: 543
Location: Wa, USA
Tim, I used the S&S kit. I am sure that the Andrews will work just fine. It just depends on your preferences. Be aware that if you bump the cams up from the stock profile that you will also have to add a Power Commander box or something similar if you have EFI.

Post Mon Jan 19, 2009 4:56 pm

Posts: 767
Location: Pa. , USA
Good imfo here guys ! not looking to make it a hotrod just want it to be right, actually i prefer motor music as long as its good stuff so cam gear wining is no problem, this is my first T-C S-T so once the weather breaks if i take a liken to it will look into all suggested upgrades, thanks again, Tim
Vintage roadracing, Class C, AHRMA # 335


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