MO-dirt-AR
Member
- Nov 6, 2001
- 39
- 0
Problem: '02 YZ250 rear wheel mud flap sucking into rear tire when bike is rolled backwards. This problem has been noted by the various dirt bike magazine tests, and occurs in my '02 YZ250.
Basically, when the bike is rolled backwards, the mud flap in front of the rear wheel (a) clicks on the knobbies like a "card in the spokes" or (b) is sucked into the tire and is pulled up from between the tire and the swingarm, so it is doubled up on top of the tire. The rider then has to re-insert the mud flap between the tire and the swingarm. :mad:
Inspection shows there is about 0.5-1.0 inches of "free play" or "air-space" between the mud flap and the swingarm. When the mud flap is pushed tight to the swingarm, thereby eliminating the "air-space", the mud flap no longer contacts the tire. <Note: Bike is new i.e. 30 minutes run time, stock chain, at factory chain slack settings>:think
FIX: The objective is to hold the mud flap tight to the swingarm and allow enough clearance for the mud flap to not contact the rear tire. One easy solution is as follows:
step 1> Loosen the (2) phillips-head screws at top of mud flap until they are in only a few threads.
step 2> Acquire a spacer of approximate dimensions 0.375 inch by 0.375 inch square and 4.0 inches long (example = pencil)
step 3> Insert the spacer behind the mud flap and on top of the bolt shafts (reference step 1), so that the spacer is between the mud flap and the air box and is resting on the bolt shafts.
step 4> Tighten the (2) phillips-head screws.
Result: The spacer forces the mud flap to pivot slightly, which presses the mud flap tightly against the swingarm so that there is enough clearance between the tire and the mud flap and it no longer catches. :eek:
Test:
Before, the mud flap was sucking into tire every time I rolled the bike backwards even one foot, even with no rider on it.
After, unloaded from trailer, and test ride for 30 minutes, roll backwards a lot, and no mud flap sucking into tire or catching at all.:)
Note on spacer: This spacer could be from many sources and materials. It could be machined from aluminum, cut from stock metal rod or stock plastic, or simply the barrel of a ball-point pen cut to fit. This shadetree mechanic tested with a piece of wood (.375X.375X4.0 inch) that was hanging around the wood bin. No patents pending and use at your own risk:p
Basically, when the bike is rolled backwards, the mud flap in front of the rear wheel (a) clicks on the knobbies like a "card in the spokes" or (b) is sucked into the tire and is pulled up from between the tire and the swingarm, so it is doubled up on top of the tire. The rider then has to re-insert the mud flap between the tire and the swingarm. :mad:
Inspection shows there is about 0.5-1.0 inches of "free play" or "air-space" between the mud flap and the swingarm. When the mud flap is pushed tight to the swingarm, thereby eliminating the "air-space", the mud flap no longer contacts the tire. <Note: Bike is new i.e. 30 minutes run time, stock chain, at factory chain slack settings>:think
FIX: The objective is to hold the mud flap tight to the swingarm and allow enough clearance for the mud flap to not contact the rear tire. One easy solution is as follows:
step 1> Loosen the (2) phillips-head screws at top of mud flap until they are in only a few threads.
step 2> Acquire a spacer of approximate dimensions 0.375 inch by 0.375 inch square and 4.0 inches long (example = pencil)
step 3> Insert the spacer behind the mud flap and on top of the bolt shafts (reference step 1), so that the spacer is between the mud flap and the air box and is resting on the bolt shafts.
step 4> Tighten the (2) phillips-head screws.
Result: The spacer forces the mud flap to pivot slightly, which presses the mud flap tightly against the swingarm so that there is enough clearance between the tire and the mud flap and it no longer catches. :eek:
Test:
Before, the mud flap was sucking into tire every time I rolled the bike backwards even one foot, even with no rider on it.
After, unloaded from trailer, and test ride for 30 minutes, roll backwards a lot, and no mud flap sucking into tire or catching at all.:)
Note on spacer: This spacer could be from many sources and materials. It could be machined from aluminum, cut from stock metal rod or stock plastic, or simply the barrel of a ball-point pen cut to fit. This shadetree mechanic tested with a piece of wood (.375X.375X4.0 inch) that was hanging around the wood bin. No patents pending and use at your own risk:p
