maintenance on a twin cam
Road Captain
Joined: Jun 2006
Posts: 621
Likes: 0
From: Newport TN
Man there are tens of thousands of HDs out there with the spring tensioners and no problems. learn how to check them. then if they get shallow install a new set. if yours is wearing preaty fast, polish the chains and reinstall with new tensioners.
My 99Ultra went 79K and I changed mine out. mine was alittle more than half wore.
all the new owners of the early twincam bikes go thru this same witch hunt when they learn about some weak tensioners.
My 99Ultra went 79K and I changed mine out. mine was alittle more than half wore.
all the new owners of the early twincam bikes go thru this same witch hunt when they learn about some weak tensioners.
Elite HDF Member
Joined: Sep 2009
Posts: 4,473
Likes: 15
From: River City Western Canada
Man there are tens of thousands of HDs out there with the spring tensioners and no problems. learn how to check them. then if they get shallow install a new set. if yours is wearing preaty fast, polish the chains and reinstall with new tensioners.
My 99Ultra went 79K and I changed mine out. mine was alittle more than half wore.
all the new owners of the early twincam bikes go thru this same witch hunt when they learn about some weak tensioners.
My 99Ultra went 79K and I changed mine out. mine was alittle more than half wore.
all the new owners of the early twincam bikes go thru this same witch hunt when they learn about some weak tensioners.
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
Outstanding HDF Member
Joined: Sep 2006
Posts: 2,334
Likes: 0
Another issue was the outer cam bearings, in particularly the rear outer. Some bearings actually grenaded sending pieces all thru the engine. If he has 20k miles I'd change out the shoes, or go gear drive but for sure change out the bearings. The engine first came out in 99' and the problems didn't show up until 2000. There was a 5 year or 50k mile HD fix on the motor. I guess the old bearing could handle the load and it didn't.
M-1097 December 21, 1999
NEW REAR CAM ROLLER BEARING ASSEMBLY
??
General
Effective December 14, 1999, a new rear cam roller bearing
assembly has been installed in both Twin Cam 88 and Twin
Cam 88B engines. To service these assemblies, or to
replace the earlier style ball bearing using the new parts,
proceed with the instructions below.
NOTE
The new rear cam roller bearing assembly will retrofit all
splined rear cams.
If the 2000 bike engine was built before 12,13,99 then you have the troublesome bearing.
I've heard its supposed to sound like a can full of marbles right before it goes.
I found this #on google, don't know if they'll still do it our you have to contact the dealer.
Call 1-414-343-4056 and give them your engine VIN. They can tell you the engine
build date.
I never got the "letter" so I should have the newer bearings.
My brother in law got the "letter" and of course it went after the 5 yr warranty was up.
Ultimate HDF Member
Joined: Jan 2008
Posts: 7,476
Likes: 5
From: Republic of Texas
Okay, here's my experience. Tensioners are crap. I changed out the tensioners at forty thousand miles. I have had gear drive for over two years and twenty four thousand miles. The old tensioner shoes with their abrasive material was doing a number on my oil pump. Could have cost me an engine. Did cost me an oil pump. I myself have never heard personally a horror story about gear driven cams but I have personally heard horror stories about the sorry *** tensioners. No more tensioners for me of any design in my HD's on my cams. No more chains on my cams. EPA mandated to quiet down the bikes crap.
Last edited by oldairboater; Oct 24, 2009 at 06:08 AM.
Elite HDF Member
Joined: Sep 2009
Posts: 4,473
Likes: 15
From: River City Western Canada
Found this while researching the topic
Tech Tips Harley-Davidson Twin Cam Tensioner Q&A
We recently received a tech question from one of our readers, which I felt should be addressed by someone who is considered one of the best Harley-Davidson technicians in the Midwest, 'Dyno' Mike Wilson of Dyno Mike's Dynamic Chassis. Question: Lately there has been a lot of press about late model Twin Cam tensioner wear and failure. I ride a 2002 Dyna FXDX with 37K miles on her. Most of the mileage I have acquired is highway miles (85%). My friend Dave has a 2001 Road King with 30K miles on her and had a recent service done to his bike and had the Twin Cam cover opened and had the tensioner examined. The service department had given him a positive feedback, stating that his tensioners were fine and there was no sign of wear. His bike like mine has stage 1, with no engine mods. The articles and news release I had read lately had most of the Twin Cam tensioner failure from southern states (Arizona, Florida, California) with stage 1 and engine mods. I dont know, but I think that this cam tensioner failure and wear has to do with climate, modification, and service. I myself use Syn tech 3 H-D oil since my 1K break in. I would appreciate feedback on this issue for Twin Cam owners that have over 25K miles on their machines. I feel that these articles are not noteworthy, because the issue at hand is not researched enough. Sure there are many variables involved; however, I think that they should not scare the many Twin Cam owners because a small percentage of these late models are having problems. Moreover, they blame H-D for poor design for these factory tensioner and promoting aftermarket replacement products. The way I see it, H-D had spent millions in the development and research with the Twin Cam motor (FATHEAD) that I have confidence that this is isolated issues. Lastly, with my experience, I have had no problems with the current crop of H-D machines that we had purchased in 01 and 02. Both bikes are running good, and I keep a strict maintained schedule on both my machines.
Dyno Mike: This is a very commonly asked question and a big concern of all the Twin Cam owners. Being in the performance field for over 10 years I have personally looked inside hundreds of Twin Cam motors and have seen first hand a variety of wear patterns on several internal parts.
First, the Twin Cam had the problem with the cam chain gear sprocket bolts, which was actually more of a key way problem in the gear itself. I saw several that failed when the bolt was still intact. The key in the big gear only had about 20 percent engagement in the shaft. Harley finally did away with this design and replaced it with a splinted shaft and gear, which solved this problem.
Next, was the B motors and the threat of the balancers being over-revved. I personally saw only one motor failure from this and the problem existed only because the shaft that turned the balancing weight chain gears only engaged about halfway through the drive gear. This was caught and redesigned halfway through the production year in 2000. Im not sure that 7000 RPM ignition modules are that harmful to the B motors especially if you realize that lots of metric bikes have balancing weights that turn in excess of 11,000 RPMs. All the motors I build have a 7000-RPM limit in the A and B motors. I stand behind the motor for one full year regardless of mileage. For example, I shift my 103 cubic inch B motor in my Fat Boy at 7500.
Next came the chain tensioner issue, and this is why I dont worry about mileage. Ive seen motors with 2000 miles on them with two broken or worn tensioners. Ive also seen motors with 75K on them with virtually no wear whatsoever on the tensioners. From what I have experienced, the way you ride or what oil you use doesnt necessarily have anything to do with wear on the tensioners.
One possibility could be on how the cam chain itself is worn. Let me explain what I meant by that statement. The pitch on the cam gears can vary from bike to bike or more so cam to cam. When the gear pitch varies the cam chain will wear prematurely and can cause the chain to develop burns and cause the chain to stiffen up. This can eat into the soft phenolic cam chain tensioner shoes like a chain saw. I would highly recommend replacing the cam chain if you experience any wear on the tensioner itself.
Another thing you should do is inspect the oil pump for scratches on the return side of the pump, because once you have any wear on the internal engine components the oil pump on the Twin Cams can really suffer. Remember the Harley motors are really dry sump motors like what racecars have. The oil is held in a remote location, and if the pump gets worn or has any scratches in the return side, the motor will retain oil and cause rapid power loss. I recommend checking the cam chain tensioners every 10,000 miles.
If you have questions or need any further assistance with this problem, feel free to call Dyno Mike Wilson at (816) 322-0379 or e-mail him at dynomikewilson@aol.com.
Mike and I agree that preventative maintenance is not only a good idea but also a safe and smart way to take care of your motorcycle.
B-safe out there!
Dave Miller
We recently received a tech question from one of our readers, which I felt should be addressed by someone who is considered one of the best Harley-Davidson technicians in the Midwest, 'Dyno' Mike Wilson of Dyno Mike's Dynamic Chassis. Question: Lately there has been a lot of press about late model Twin Cam tensioner wear and failure. I ride a 2002 Dyna FXDX with 37K miles on her. Most of the mileage I have acquired is highway miles (85%). My friend Dave has a 2001 Road King with 30K miles on her and had a recent service done to his bike and had the Twin Cam cover opened and had the tensioner examined. The service department had given him a positive feedback, stating that his tensioners were fine and there was no sign of wear. His bike like mine has stage 1, with no engine mods. The articles and news release I had read lately had most of the Twin Cam tensioner failure from southern states (Arizona, Florida, California) with stage 1 and engine mods. I dont know, but I think that this cam tensioner failure and wear has to do with climate, modification, and service. I myself use Syn tech 3 H-D oil since my 1K break in. I would appreciate feedback on this issue for Twin Cam owners that have over 25K miles on their machines. I feel that these articles are not noteworthy, because the issue at hand is not researched enough. Sure there are many variables involved; however, I think that they should not scare the many Twin Cam owners because a small percentage of these late models are having problems. Moreover, they blame H-D for poor design for these factory tensioner and promoting aftermarket replacement products. The way I see it, H-D had spent millions in the development and research with the Twin Cam motor (FATHEAD) that I have confidence that this is isolated issues. Lastly, with my experience, I have had no problems with the current crop of H-D machines that we had purchased in 01 and 02. Both bikes are running good, and I keep a strict maintained schedule on both my machines.Dyno Mike: This is a very commonly asked question and a big concern of all the Twin Cam owners. Being in the performance field for over 10 years I have personally looked inside hundreds of Twin Cam motors and have seen first hand a variety of wear patterns on several internal parts.
First, the Twin Cam had the problem with the cam chain gear sprocket bolts, which was actually more of a key way problem in the gear itself. I saw several that failed when the bolt was still intact. The key in the big gear only had about 20 percent engagement in the shaft. Harley finally did away with this design and replaced it with a splinted shaft and gear, which solved this problem.
Next, was the B motors and the threat of the balancers being over-revved. I personally saw only one motor failure from this and the problem existed only because the shaft that turned the balancing weight chain gears only engaged about halfway through the drive gear. This was caught and redesigned halfway through the production year in 2000. Im not sure that 7000 RPM ignition modules are that harmful to the B motors especially if you realize that lots of metric bikes have balancing weights that turn in excess of 11,000 RPMs. All the motors I build have a 7000-RPM limit in the A and B motors. I stand behind the motor for one full year regardless of mileage. For example, I shift my 103 cubic inch B motor in my Fat Boy at 7500.
Next came the chain tensioner issue, and this is why I dont worry about mileage. Ive seen motors with 2000 miles on them with two broken or worn tensioners. Ive also seen motors with 75K on them with virtually no wear whatsoever on the tensioners. From what I have experienced, the way you ride or what oil you use doesnt necessarily have anything to do with wear on the tensioners.
One possibility could be on how the cam chain itself is worn. Let me explain what I meant by that statement. The pitch on the cam gears can vary from bike to bike or more so cam to cam. When the gear pitch varies the cam chain will wear prematurely and can cause the chain to develop burns and cause the chain to stiffen up. This can eat into the soft phenolic cam chain tensioner shoes like a chain saw. I would highly recommend replacing the cam chain if you experience any wear on the tensioner itself.
Another thing you should do is inspect the oil pump for scratches on the return side of the pump, because once you have any wear on the internal engine components the oil pump on the Twin Cams can really suffer. Remember the Harley motors are really dry sump motors like what racecars have. The oil is held in a remote location, and if the pump gets worn or has any scratches in the return side, the motor will retain oil and cause rapid power loss. I recommend checking the cam chain tensioners every 10,000 miles.
If you have questions or need any further assistance with this problem, feel free to call Dyno Mike Wilson at (816) 322-0379 or e-mail him at dynomikewilson@aol.com.
Mike and I agree that preventative maintenance is not only a good idea but also a safe and smart way to take care of your motorcycle.
B-safe out there!
Dave Miller
Thread Starter
|
Seasoned HDF Member
Joined: Mar 2008
Posts: 5,134
Likes: 146
From: texas
wow that is alot of info.i think imight just recomend to my friend that he take it in to a bike shop.i dont want to stumble through helping him either.mostly i could probably do the work but i would be a little afraid of overlooking somthing else.---i guess if he wentthe gear route their would nt be much to overlook though.
if what was said directly above about the pitch on the cam gears varying from bike to bike so much so that it scars up the chain eneough to chew up the tensioner....man that to me is totally unacceptable.seems like quality control dropped the ball big time there.i love harleys of all years but i understand why that guy i spoke of had the upside down 1.--again thanks everyone and i think the bike shop will get this one.
if what was said directly above about the pitch on the cam gears varying from bike to bike so much so that it scars up the chain eneough to chew up the tensioner....man that to me is totally unacceptable.seems like quality control dropped the ball big time there.i love harleys of all years but i understand why that guy i spoke of had the upside down 1.--again thanks everyone and i think the bike shop will get this one.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom
Verdad Gallardo
6 Weirdest Harley-Davidsons Ever Sold to the Public
Verdad Gallardo
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
senior experienced all-knowing leader of the unwise
Joined: Apr 2008
Posts: 1,957
Likes: 352
From: USA
Just because they look good doesn't mean they won't go out soon. I looked at the ones in my dyna(05) and they didn't need replacing at 34,000, i had always ran synthetic. 2,000 hot summer miles later when i put gear drive cams in, the inner tensioner was shot.
Seasoned HDF Member
Joined: Jun 2005
Posts: 12,946
Likes: 32
From: Colorado Springs, CO
I have heard about crank runout and gear drive problems.
It's gonna take alot of wear and tear for the crank to start moving, it seems.
Worst thing Harley ever did was use the spring tensioners with the crappy orange material shoes.
~Joe
It's gonna take alot of wear and tear for the crank to start moving, it seems.
Worst thing Harley ever did was use the spring tensioners with the crappy orange material shoes.
~Joe