St1100 or St1300?? Which should i buy?

[Andrew Shadow]

Based on the experiences that I have read about on this forum, I think that the condition of the bearings in the water pump and the idler pulley is more of a concern than the belt itself. In cases where a timing belt has failed, it always seems to be due to a bearing failure in one of these items that caused a belt failure rather than a belt being the primary failure.
Some people recommend replacing these items when replacing the belt as preventative maintenance.

 

[drawderm]

I don't worry about the belt on my 01 with 70K on the clock. I don't believe there has ever been a documented failure of the timing belt with less than 100K, at any age. Most everyone that changes them notes that the old belt is in perfect condition. If I was worried I'd inspect it, see if there is any visible cracks, wear, etc. But you have to be comfortable with it. I'd been more concerned with the condition of the calipers and pistons. I've seen a whole lot of crud in them when disassembled even after a fluid flush. The fluid flush ensures that there is fresh fluid that won't break down. But it really doesn't get the crud that is already there out. Same goes for the clutch/slave cylinder. Deferred maintenance in those systems requires a teardown, IMHO.

Interesting. Hadn't heard of that, but it sounds straightforward. Have any pics or video of that being done?

I would imagine the new belt would be a little bit tighter, due to wear and stretch of the old belt.

I've never done it on a bike before but ive done it on a 1.9 diesel VW passat previously! The advantage is that you dont have to worry about timing marks or bolts snapping etc. The disadvantage is that you do not get a full appreciation of the condition of the water pump and rollers etc. I will post the pic of the car belt i took at the time if i can find it..

 

[rwthomas1]

I've never done it on a bike before but ive done it on a 1.9 diesel VW passat previously! The advantage is that you dont have to worry about timing marks or bolts snapping etc. The disadvantage is that you do not get a full appreciation of the condition of the water pump and rollers etc. I will post the pic of the car belt i took at the time if i can find it..

You are a braver man than I. I happen to have a 1.9TDI and am intimately familiar with changing that belt. I wouldn't even consider doing it without the right tools.

 

[drawderm]

Pls see below of cambelt change in my car. Not sure if this possible on the ST1100 or not but i dont see why not. The cambelt is surprsjngly easy to cut along its lenght and you just rotate the engine by the crank bolt to complete the cut all the way around. When you have 50% of the width of the belt removed along its entire lenght, then you fit the new belt carefully onto pulleys without damaging the edge. You then remove the old belt with one final horizontal cut and proceed to gently ease on the new belt

 

[rwthomas1]

Pls see below of cambelt change in my car. Not sure if this possible on the ST1100 or not but i dont see why not. The cambelt is surprsjngly easy to cut along its lenght and you just rotate the engine by the crank bolt to complete the cut all the way around. When you have 50% of the width of the belt removed along its entire lenght, then you fit the new belt carefully onto pulleys without damaging the edge. You then remove the old belt with one final horizontal cut and proceed to gently ease on the new belt

Wow, OK, never seen that done, but theres no reason why it wouldn't work. I still don't like it due to the fact that I want to spin all the idlers, waterpump, etc. to assess the condition of the bearings. But it would certainly work in a pinch. I wouldn't do it on a VW TDI as the waterpumps are notorious for failure and most change them with the timing belt.....

 

[drawderm]

Wow, OK, never seen that done, but theres no reason why it wouldn't work. I still don't like it due to the fact that I want to spin all the idlers, waterpump, etc. to assess the condition of the bearings. But it would certainly work in a pinch. I wouldn't do it on a VW TDI as the waterpumps are notorious for failure and most change them with the timing belt.....

Aww yes, i agree about the possible downsides. Now i don't wish to turn this into a conversation about Volkswagen Passats but I agree about the water pump. However in my situation I know that 40,000 miles previously, I had replaced the water pump and bearings with genuine parts so I know its good for many more mls. Nothing can go wrong with this procedure because you're not removing the old belt until the new belt is halfways on, and by that stage, i dont believe the belt timing can't go out of plonk because it is being held by the old and new belt. You are not even releasing the tentioner. However, there is nothing stopping you from checking the timkng marks afterwards with a jig on crank and drill bit in the hole on camshaft etc..