Timing Belt

I watched a video of a fellow changing the timing belt on the front of the engine of the ST which brought up a couple of questions. What is the life span of this fiber belt and does it need to be changed on some schedule? Would a timing belt failure lead to great damage to the engine; would the pistons hit the valves? In the video the fellow was changing the belt and the water pump. Is that a normal repair?

Thunderchief said:

I watched a video of a fellow changing the timing belt on the front of the engine of the ST which brought up a couple of questions. What is the life span of this fiber belt and does it need to be changed on some schedule? Would a timing belt failure lead to great damage to the engine; would the pistons hit the valves? In the video the fellow was changing the belt and the water pump. Is that a normal repair?

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90k miles. Bad things happen when they break. Most change out the water pump when doing it. BUT, this is for st1100s. 1300s have a timing chain.

I believe that the Honda spec for the t belt is 80,000 miles without a specific time limit to get to that number. I changed mine on my '98 when I bought it in '12 because I wanted to have a fresh start with the bike. My ST only had 35,000 on it when I changed the belt and it still looked brand new. I put a gates brand in because it is a little cheaper and still a quality belt. The original looked so good, I put it in the empty gates box and put it on the shelf...Just in case. The ST has an interference engine so if the belt snaps, stuff is going to get bent. A lot of people change the water pump with the timing belt because you are already half way there when you are changing the belt. The water pump is just about the entire left front cover =of the engine and is quite costly as I remember...I think upwards of $300. I didn't change mine when I did the belt.

From the manual, the recommendation is 90,000 miles or 144,000 kilometres - no time limit. I can't recall ever seeing a thread anywhere where a belt broke and the vast majority of those that report on older belts being changed out say they still look brand new. I have heard of one where the belt had somehow slipped off a pulley slightly and had been worn to half of its original width, when it was discovered.

You can go into the left side of the engine and easily get a look at the belt by removing some plastic and a couple of parts. If you take out the spark plugs and remove the crankshaft timing inspection cover, you can rotate the engine by hand to get a look at the whole belt.

If you know the coolant has been replaced often over the years - with a SILICATE free coolant - the water pump should still be fine. The only problems you can have with the pump is a worn bearing seal, caused by using a non silicate coolant, or a corroded impeller caused by well overdue coolant changes. The shaft bearing itself seems bulletproof. Never heard of a failed one myself. You didn't mention how many miles you have on your bike, but, IMO, a water pump should be good for at least 150 - 200,000 miles

I have mine changed at 100,000 miles (got one coming up on my 02 shortly). The belt that came out of my 97 at 100,000 looked just fine and the water pump and pulley were fine - but it is good to check them while you are in there. The belt change is one of the few things I let a shop do because if they mess it up and really bad things happen, it's their nickel and I could get a 'new' engine out of the deal. Also, if there's an oil leak or a anti-freeze leak when they're done, they get to go back in there instead of me. I also let them check the valves and change all the fluids while they have it. But I do remove most of the bodywork before I bring it in to 'protect' it and make sure I have all the right fasteners when it's over.