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-   -   Correct Drive belt deflection on side-stand (https://www.rswarrior.com/forums/13-technical-discussion/306328-correct-drive-belt-deflection-side-stand.html)

ThingFish 11-01-2019 10:09 AM

Correct Drive belt deflection on side-stand
 
Guys I see a number of posts here where correct drive belt deflection is mentioned as being 1/2inch-3/4inch of slack on the sidestand...that is 12.7mm-19.05mm with 10 pounds upwards push force (4.5kg)
But in my owners manual it states to use the marks on the belt drive bottom cover which are marked in increments of 5mm and deflection should be 6mm-8mm (or 0.24-0.31 inches) on the side stand with 10 pounds upwards push force. That is a BIG difference!! Which is correct? The manual surely?

Someone else here (Snowboy) says he has half an inch slack upwards and half an inch slack downwards making it a total of 1 inch slack. Quote "With the bike on the side stand, I always adjusted mine so the belt could move 1 inch total (" up and " down)" Unquote

freeezzzz 11-01-2019 11:48 AM

I also agree with the opinion that the manual indicates an excessively strong tension of the drive belt. I do less than indicated in the manual. But I can’t say anything instrumentally, although I have a tensometer. I used to use a strongly sagging belt, so much so that I could feel the slaps of its tension during acceleration. Unpleasant, but not fatal. But when the belt was pulled as said in manual, I noticed tangible wear on the driven pulley in just 8 thousand kilometers. Moreover, such a tension of the belt contributes to the damage of the bearings of the wheel axis and the middle gear.

In general, I look at the manual, take a tensometer and do a little less)))

arizonawarrior 11-01-2019 10:19 PM

As the pulleys rotate, the belt tightness changes. I've had excellent results using the service manual instructions and specs. These procedures start with finding the tightest spot on the pulley's rotation. The rest of the spots are more loose. When you do this set-up right, and it's all buttoned-up, you can always check all the points on the belt's rotation and discover something.

rij1 11-02-2019 02:37 AM

I always set them to 1/2" - 10lb - on side stand if not 1/4" - 10lb - on side stand.

ThingFish 11-02-2019 03:42 AM

Quote:

Originally Posted by rij1 (Post 3872382)
I always set them to 1/2" - 10lb - on side stand if not 1/4" - 10lb - on side stand.


So which is it? 1/2" or 1/4"?

rij1 11-02-2019 03:44 AM

Quote:

Originally Posted by ThingFish (Post 3872388)
So which is it? 1/2" or 1/4"?

Usually 1/2" but that's my max.

ThingFish 11-02-2019 08:59 AM

Quote:

Originally Posted by rij1 (Post 3872390)
Usually 1/2" but that's my max.

So thats a 1/2 inch up and a 1/2 inch down so in total 1 inch slack....seems a bit too loose to me

arizonawarrior 11-02-2019 09:26 AM

When checking belt tension you push the belt 'up' using a 10-pound gauge until it deflects the desired / specified distance. It's the same tension no matter if you deflect the belt up or down. It is not compounded.

Many do not rotate the rear wheel in order to find the spot where the belt deflects the least (tightest spot) and guage at that point to spec. I suspect not finding the tight spot and instead using 1/2" at any random spot has a chance of being close enough. But on the off chance your random spot is the loosest spot, you would tighten it and make the tightest spot even tighter. The other side of the equation if using random spot means there could be enough slack to cause slap on WOT and snap the belt. This isn't rocket science. Too tight and the bearings and pulleys and belt all suffer. Too loose and the belt breaks while riding this bike the way God intended. Belts are a massive pita to source and install on the road, I'm mystified why more people don't take advantage of a simple engineered sequence to leverage the bike's design for wear items like the drive belt. If you choose to remove the belt guard it still only takes a moment to grab a flat ruler to gauge deflection to some extent.

rij1 11-02-2019 02:56 PM

Quote:

Originally Posted by ThingFish (Post 3872392)
So thats a 1/2 inch up and a 1/2 inch down so in total 1 inch slack....seems a bit too loose to me

You just push/ measure in one direction (usually up). 1/2" max. If I'm working on there friend bikes I set to 1/4" but mine I set to 1/2".
If you think it's too loose for you set it to factory specs or to 1/4".


Quote:

Originally Posted by arizonawarrior (Post 3872394)
When checking belt tension you push the belt 'up' using a 10-pound gauge until it deflects the desired / specified distance. It's the same tension no matter if you deflect the belt up or down. It is not compounded.

Many do not rotate the rear wheel in order to find the spot where the belt deflects the least (tightest spot) and guage at that point to spec. I suspect not finding the tight spot and instead using 1/2" at any random spot has a chance of being close enough. But on the off chance your random spot is the loosest spot, you would tighten it and make the tightest spot even tighter. The other side of the equation if using random spot means there could be enough slack to cause slap on WOT and snap the belt. This isn't rocket science. Too tight and the bearings and pulleys and belt all suffer. Too loose and the belt breaks while riding this bike the way God intended. Belts are a massive pita to source and install on the road, I'm mystified why more people don't take advantage of a simple engineered sequence to leverage the bike's design for wear items like the drive belt. If you choose to remove the belt guard it still only takes a moment to grab a flat ruler to gauge deflection to some extent.

Good explanation...

ThingFish 11-02-2019 07:03 PM

Thanks for the feedback...My belt I just checked at a few spots.....tightest is about 1/3" and loosest spot just a bit less then 1/2". Belt makes no weird noises when I free wheeled down a hill this afternoon with engine switched off, in fact I dont even hear the belt.


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