Hello Gents,

I've got a wm-fx5 (ex5 with radio) and I cleaned head, pinch rollers/capstans, all the pulleys, and put in a replacement belt and have really bad wow and flutter. I got the belts in a set from DocP, so I've tried several different sizes. the belts do have a rectangular cross section and are prone to twisting. The twists seem to cause a vibration in the belt which causes w&f. Ive tried to get all the twists out but have had little success.

I've noticed that the pulley towards the top of the player has a lip on the bottom and it seems that the belt is rubbing it. also this is a pretty thin belt (less than 1 mm) and I'm sure it is the right diameter. Maybe I need a round belt?

What is the condition of the pinch roller? Aside from it being cleaned, is it perfectly smooth or are there indentations from the capstan, is it cylindrical or barreling out in the middle, is it rock hard or is it soft and supple? How was it cleaned, did you use any rubber restore treatment such as platenclene on it afterwards?

pinch rollers are supple and clean, capstans are clean, I "flossed" the pulley grooves with string, I cleaned the belt with rubber cleaner. This all seemed to help but there's still a bit of flutter, but I'm still working all the twists outta the belt. this thing is pretty touchy.

Did you de-grease the pulley grooves with alcohol, either denatured ethyl alcohol or isopropyl alcohol? Is there any corrosion on the brass pulleys? If so, you will need to polish that out first before de-greasing it. You may also need to clean the belt of any contaminants.

Yep, I polished and degreased the pulleys, and cleaned the belt. I'm convinced that I've got a funky belt.