Right Cam Gear Timing Belt Guide ??

Jim Van

Jim Van

Joined
Sep 10, 2011
Messages
2,210
Location
West Michigan
Bike
'98 ST1100
STOC #
8470
I have an extra Timing Belt Guide Plate, ( Officially Item #15 : Guide, Timing Belt Driven Pulley ) like the one that's mounted over the left cam gear. So, I'm thinking of installing it over the right cam gear.

Seems to me having a guide plate on each pulley should help "stabilize" the timing belt more than just one on the left side. And what's so magic about having it on the left side instead of the right side ??

Anyone have any comments ??
 
I have not heard of any st timing belt issues. I'm sure the engineers at Honda are a lot smarter than you or I
 
Jim Van said:
OK, but why is there one on the left side, but not the right side from the factory ???
Click to expand...

my guess is one guide will prevent the belt from moving away from its pulley, and the tension on the belt takes care of everything else, so more guides would be redundant.

Given the weight of the ST, and the low performance design of the engine, the reason is NOT that the Honda engineers were hesitant to add extra weight and inertia with another guide.
 
Since I have an extra, I might as well put it to use. I'm going to mount it, to see what happens next. :) Can't hurt ( I hope).

Wish me luck. And I'll know I probably have the only ST1100 out there with two guide plates. So if you see me on my ST1100 with a smile on my face, you will know why ;)
 
Last edited:
dwalby said:
what exactly do you think you will gain by this experiment?
Click to expand...

Longer timing belt life. The timing belt should "wander" less with the extra guide plate. It can only help. I can't see any down-side. Worst case is that I might decide to remove the extra guide plate if something unforeseen occurs, which I doubt will happen. But that will be easy to do, just remove the plastic cover on the right side.
 
Last edited:
These belts are fairly stiff 'in plane'...and are short. Only the one guide is necessary as the other pulleys are 50 or fewer teeth away from the left cam pulley or adjacent pulley.
Don't see what an additional guide will hurt but I don't think it's necessary.
 
My thinking comes from the fact that hundreds of thousands of 1100 engines have proven bullet proof over 26 years, with extremely few ever having timing belt failures, especially being caused by a lack of another guide on a pulley! Maybe you should also make guides to place on the idler and tensioner pulleys. I know you are retired and have a lot of spare time on your hands, but this exercise is pointless.
 
Jim Van said:
Longer timing belt life. The timing belt should "wander" less with the extra guide plate. It can only help. I can't see any down-side. Worst case is that I might decide to remove the extra guide plate if something unforeseen occurs, which I doubt will happen. But that will be easy to do, just remove the plastic cover on the right side.
Click to expand...

Longer timing belt life, huh, the things look new after 20 years and 100k miles, good luck with that.

Wander less, what proof do you have that it wanders at all with the single guide?

potential downside: maybe the belt does wander a bit on the right pulley and without a guide plate its no harm, no foul. But with your clever modification the belt starts chafing on the guide plate and frays itself into self-destruction. Self-inflicted timing belt failure, engine destroyed, for nothing. Not likely that this would happen, but in my mind, why give it the one-in-a-million chance that it could happen? You're not fixing anything, so why even go there?

If a professional engine designer with intimate knowledge and testing of his design purposely left it off of that pulley, why would you second-guess that decision for no real benefit? That really was hard for me to type because I often challenge the Honda engineers on their decisions like the floppy saddlebag mounts, requiring crazy amounts of plastic removal to access the radiator cap, etc. But one thing I've never challenged is that the ST engine is totally bulletproof as-is, so why mess with anything about it?
 
The single guide may have to do with the fact that the exit of one pulley has the belt under tension whereas the entrance to the other pulley has the belt under relatively less tension, all depending somewhat on belt and pulley tolerances.

FWIW, I have to agree with the three previous posters. You're not solving any problem and you may be causing one. I wouldn't do it, unless you have a spare engine.
 
But I have the spare guide plate..... I hate to see it go to waste. I'm puttin that sucker on !! I can get a spare engine off Ebay , if I have to.
 
Last edited:
You have a spare because of your obsession with changing out parts that never needed changing to begin with. Is being so obsessed about PM really saving you money? Put it in a drawer, out of sight and maybe you can forget you have it.
 
Mikedo said:
Jim, I have no opinion on the guide plate. I love your "Get er done" manner. Damn the torpedoes, ramming speed. Looking forward to updates.
Click to expand...

Yes, we have fun on this Forum, at times. It's amazing how worked-up some members can get interacting with others. Don't you agree ??

I put the extra guide plate on today ( seriously ) and have all the front plastic covers back on and take fully responsibility for my actions. If the belt explodes, I hope the covers aren't damaged.
 
You must log in or register to reply here.
Top Bottom