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Original Post (Thread Starter)
#784241 08/22/2023 6:07 PM
by Scartans72nad
Scartans72nad
How do you cure the drive belt high pitched screech which occurs during any acceleration with the S3? Is it the belt being too tight, too loose or not centered? Help!
Liked Replies
#784343 Aug 23rd a 08:33 PM
by Scartans72nad
Scartans72nad
What I've learned so far - to add to what Red 3 has said, to adjust the drive belt, loosen the axel bolt ( 24mm on one side and 36mm on nut side) loosen jam nuts on fore-aft axel adjusting bolts. you can then adjust the belt tightness. At this point you will need the Apple App called "Carbon Drive" by Gates who makes the belts. The magic numbers are 72-84 HZ -you take a spanner and repeatedly hit the middle of the belt suspended area and record the noise with your iPhone. this sounds bizarre but it works. Mine is at 79 HZ and there is now very little screech.
I f you eyeball or actually align your front wheels straight and then adjust the steering wheel straight, then go for a drive and your steering wheel is not straight, then you are "crabbing". This means the rear wheel is not adjusted straight. This requires Trial and Error with the axel adjusting bolts or some other ingenious method. Getting it straight should make the belt track in the middle of the sprocket(s). This raises the Question- Is the BB sprocket adjustable, ie is the bevel box adjustable. I am assuming my BB is straight and I am only adjusting the axel adjusters.
Finally my S3 was twitchy at speeds greater than 60 mph so I checked the toe in. This should be 0.5 degrees. At 28 inches apart ,the diameter of the front tires, the distance between the front and rear ends of the sticks that I attached to the tires should be 6mm. the front shorter than the rear- toe in. Mine was only 3 so I adjusted the tie rods until I had 5+mm. This seems to have fixed the problem. My S3 is now a quiet straight shooter!
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#784262 Aug 22nd a 09:47 PM
by sospan
sospan
I had a Plus 8 and it was a known quirk. When mine developed a squeal I took the belt off, cleaned all the pulleys and wiped the belt ( it was nearly new and good condition) clean. Replaced and tensioned. No squeals for 10 years! This was the simple first tion. A second option on Plus 8’s was fitting a slightly narrower belt ( see gomog).
Try the tension/cleaning options first before checking pulley alignments.
The KISS principle. I had a poster on my office wall....
Keep
It
Simple
Stupid
!
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