Timing belt. It's not the miles, but the years. If it's not broke, should I fix it?

[Ned in Utah]

The 1994 ST1100 I picked up last year only had 15,000 miles on it. It was a hanger queen, the guy was a little vertically challenged, so just moved it around a lot instead of riding it. Other than a few "moving around" scrapes and scuffs it's in great shape as it's been indoors all it's life.

I'm planning a trip to Alaska next year, so my question to all you ST gurus is this, the bike only has 21,000 miles now, but it does have 24 years on it. Should I think about replacing the timing belt before the trip or do you think it's ok?

 

[SMSW]

It is likely fine, but IIRC, my 89 Honda Accord had a mileage/time rated belt. After 24 years, I'd change it for peace of mind if nothing else, especially when you consider what can happen if the belt breaks at speed.

 

[jettawreck]

Visual belt condition is not much of an indicator unless there is an obvious defect or flaw ready to fail. I have no real experience with Honda motorcycle timing belts but plenty of past and present VW TB maintainence. In those applications it's seldom the belt that fails first. The tensioner, waterpump, or a roller/idler bearing fails and causes a "belt failure". Dayc, Gates and Continental supply most of the replacement (and probably OEM) belts and recommend replacement after 7 years if the mileage service interval isn't yet reached.
On any interference design engine it doesn't make sense to exceed the service interval or suggested life. Valve, head, piston and even rod damage can pretty much mean an end to an engine as it's often costlier to repair than the vehicle/bike is worth.
Change it and any recommended parts in the belt system path. Then it's done and ready for service for a long time w/o worries.

 

[Uncle Phil]

I just had one of my 97s in recently for the 100,000 mile service. It had the original timing belt and it looked as good as a new one. I save my old ones and so far everyone of them are in excellent shape. You can flex them and see no cracks or deformities in them.

 

[Upt' North]

The 1994 ST1100 I picked up last year only had 15,000 miles on it. It was a hanger queen, the guy was a little vertically challenged, so just moved it around a lot instead of riding it. Other than a few "moving around" scrapes and scuffs it's in great shape as it's been indoors all it's life.

I'm planning a trip to Alaska next year, so my question to all you ST gurus is this, the bike only has 21,000 miles now, but it does have 24 years on it. Should I think about replacing the timing belt before the trip or do you think it's ok?

Ned, I don't think I'm a mind reader but I can hear, "if I don't change it and those lovely valves smash into those lovely round pistons how stupid would I feel". Like UP says it'll probably be fine and dandy for a long while yet but if you're the sort of guy who's gonna fret about it, then you know the answer.
But fact is I've never heard of one going and yes Jettawreck is right it's normally an ancillary that will kill it.
Hope it helps.
Alaska! Wished I was going, new cambelt or not.
Upt'North

 

[Oldbikefixr]

There are several discussion threads on this site, just search on 'timing belt'. Lots of great info. Bottom line is that ST1100 belts seem to be mileage related failures, not time...but then, few of us have worked on abused or improperly stored bikes. The Gates 325 belt is a suitable replacement for the Honda part...Looks identical.
If you aren't familiar with the 1100, belt replacement is a good way to become familiar with it and get to inspect over half the items that can fail due to age or neglect. Do the change and you won't have a 'I shoulda done that' failure.....peace of mind.

 

[John OoSTerhuis]

JMHO, but the belt is just fine, even at that age, and so are the idler and tensioner which would be the cause of any belt failure. If you are mechanically inclined and would be doing the R&R yourself, it might be something you’d enjoy doing, but if you’d be paying a shop to do it ($$$) it’s not needed. Again, JMHO.

Pull the little Timing Hole Cover and if there’s not frayed strands of belt (THE evidence of impending failure — bearing failure/belt not running true/rubbing), then put it out of your mind and just GO RIDE! Go to Alaska (and maybe the Arctic Circle, BTDT) in confidence. These are great motorcycles!!!

Edit: I know of only one bearing/belt failure on a high mileage ST1100. Both my belts (90K, 180K); and idler, tensioner bearings, and water pump (180K) look and feel like their replacements.

Regards, John

 

[Upt' North]

The 1994 ST1100 I picked up last year only had 15,000 miles on it. It was a hanger queen, the guy was a little vertically challenged, so just moved it around a lot instead of riding it. Other than a few "moving around" scrapes and scuffs it's in great shape as it's been indoors all it's life.

I'm planning a trip to Alaska next year, so my question to all you ST gurus is this, the bike only has 21,000 miles now, but it does have 24 years on it. Should I think about replacing the timing belt before the trip or do you think it's ok?

Ned, totally unrelated, but change the bulbs before you go, many will probably be originals. From experience, yes I didn't change them, long days and vibes will sort out the wheat from the chaff. It is much easier to change them in the garage this winter than on the side of the road next summer.
Enjoy.
Upt'North.

 

[John OoSTerhuis]

Ned, just remembered you have a ‘94. If you haven’t upgraded the alternator, do all the normal tests, cleaning, inspections etc. of the system; cut out the red 3P and install a digital voltmeter that reads in tenths of a volt. TruST me.

John

 

[Ned in Utah]

Ned, just remembered you have a ‘94. If you haven’t upgraded the alternator, do all the normal tests, cleaning, inspections etc. of the system; cut out the red 3P and install a digital voltmeter that reads in tenths of a volt. TruST me.

John

Thanks for the advice John. I'm assuming by "Red 3P" you're referring that red 3 prong plug behind the left side cover that sort of looked like it was getting fried? If so, I already did that when I replaced the leaking alternator o ring. Probably should have up graded the alternator, but was a real newby at the time. Not that I'm much better now!

 

[Erdoc48]

I’m one that changed the timing belts on both ST’s (the 94 and 00)- both ~ 33K miles because of age and as UP said above, the belts looked new (no cracking and the lettering from Honda was still visible). I’m a little obsessive when it comes to maintenance, so that’s why I did them (also did the hoses and elbows under the carbs- they looked to be in very good condition as well). I feel better that it’s all done and other than oil changes, I don’t have to do any other maintenance for a long while, but much of it was probably not needed. I would recommended changing all the fluids (brake, clutch, rear diff, and even the coolant as well as the oil), but the other stuff can wait. Ride on and don’t worry!

 

[dwalby]

also did the hoses and elbows under the carbs- they looked to be in very good condition as well).

sorry for the slight thread hijack, but this is a maintenance item that I wouldn't head off to Alaska without doing on a bike that age. While the TB will last seemingly forever (mine looked like new just like everyone else's) these coolant hoses will split and puke all the coolant in a matter of seconds, no warning, no limping home or to the nearest shop. The fact that the bike is very low mileage probably helps them last a bit longer than average (they seem to bulge over the years presumably due to engine heat) but not worth gambling on for a ride of that distance.

 

[Erdoc48]

^^Good point.

 

[red one]

Haven't looked at mine. But every time someone post about a timing belt I get paranoid

 

[Andrew Shadow]

In my opinion 24 year old rubber is 24 year old rubber and it deteriorates whether it is being used or not. I would have a different opinion if it were 10 years old but at 24 and for the cost of it why take the risk, however minor it might be, when departing on such a long trip that can be ruined by it failing? Change it for the same reason you should change the coolant hoses- so you can forget about them and enjoy your trip.

 

[Bush]

Does a belt sitting inside an engine, with little use over several years, decades even, deteriorate more, or faster, than a brand new belt that may have sat on a shelf in a warehouse for several years? Do we know how long it has been since the OEM belts, still available from the dealer, were made?

That's what I was wondering today, when thinking of changing out my 22 year old belt that will probably look as good as new too and is still below the mileage limit.

 

[Oldbikefixr]

My pre-St1100 rides were 1978 GL1000's that I rebuilt. I had valve damage to one due to a failed timing belt. Honda manual said replace at 5 years or 50000? miles. When I restored the bike in 1996, it only had 25000 miles on it, so I replaced the belts (2 of them) with 'new'. One broke after just 17000 miles, bending both exhaust valves in the left cylinder. Three teeth had broken away from that belt. My new belts had probably been sitting on a distributor's shelf for as long as 21 years. As a result, I'm a bit cautious about belts.

That aside, the old style belts and ST1100 style are very different.

The GL belts have teeth that mimic machined parts, much like the drive belt on the blower of a drag racer. There are crisp angles at the root and crown of the teeth. The cross section looks as though it could have been machined from a thicker band of material.

The ST style belt has 'wavy' teeth molded with no sharply defined corners. You can see the layers in the belt conform to that wave cross section. These teeth will not shear off the belt. The belt I removed from mine was almost indistinguishable from the new Gates belt I replaced it with. Same flexibility, no indication of wear on the 24 year old belt vs the 8 month old belt. The writing on the flat side were still legible. This design belt is not as likely to fail mechanically as the older toothed designs and time doesn't seem to alter the rubber composition.

Draw your own conclusions about replace/don't replace. It will probably not be a bad decision either way.

 

[jettawreck]

Timing belts typically contain virtually no "rubber". It's almost exclusively synthetic strands and materials. When you handle them they "feel" nothing like conventional flat serpentine or v belt drives. Most will have a manufacture date code that would be worth checking out. It's also very possible that you would get a better chance of getting "fresh" product from aftermarket, which probably supplied the OEM part anyways, than from dealer stock if in their inventory.

 

[dwalby]

for the cost of it why take the risk, however minor it might be, when departing on such a long trip that can be ruined by it failing?

Because many, probably dozens, of people here have already changed their 22 year old belts and reported back that it was essentially a waste of time.

As was mentioned before, if you buy the $35 Gates belt and do the work yourself then its probably worth doing, but if you're looking at paying a dealer hundreds of dollars to do the job that's probably not money well spent.

In my case, I replaced everything under the front cover, TB, pulleys, water pump because I figured do it once every 20 years and forget it, but paying a dealer to do that would have cost over $1k I'm guessing, and the bike's only worth $1500-2000 anyway. Also, my water pump bearing was making noise, so it forced my hand.

 

[Uncle Phil]

Because many, probably dozens, of people here have already changed their 22 year old belts and reported back that it was essentially a waste of time.

As was mentioned before, if you buy the $35 Gates belt and do the work yourself then its probably worth doing, but if you're looking at paying a dealer hundreds of dollars to do the job that's probably not money well spent.

In my case, I replaced everything under the front cover, TB, pulleys, water pump because I figured do it once every 20 years and forget it, but paying a dealer to do that would have cost over $1k I'm guessing, and the bike's only worth $1500-2000 anyway. Also, my water pump bearing was making noise, so it forced my hand.

And what I am founding out is that Honda Dealers do not want to work on ST1100s because of their 'age' at any price. So unless you are going to do the work yourself, you'll spend more than the bike is worth to fix something that probably does not need fixing. I've taken all three of my ST1100s to Alaska with high miles and the original timing belts without an issue.

http://www.unclephil.us/Alaska2004Home.htm
http://www.unclephil.us/Alaska2012Home.htm
http://www.unclephil.us/Canada2013Home.htm

I'd be more concerned about picking a set of tires that will get you up there and back because an 'on the road' tire change can be painful, expensive, and time consuming. I use the BT020 Bias (goes on the big BMW KLT - same size) and I've heard good things about the Michelin Commander but I've not used one yet.