Vintage Dirt Bike Q & A

Well I have been fighting my kick starter for the last 6 months but I picked up the bike for only 300 bucks so I have been dealing with it (slipping, not grabbing every kick, have to push inward to get it to grab well). But now the bike is in awesome running order and the kick starter is beginning to agravate me. So I'm pretty sure it just needs the spring behind the ratchet but just to be safe I bought the whole assembly off ebay.

Now my question is what else will I need to replaced (gaskets, seals etc.) while getting to the kick start?

oh yea, does an 89 cr250 even count as vintage? probably not but I figured this was my best bet

You are going to need a new gasket that goes between the case and the clutch outer
case cover (the big one with the oil cap). I would also replace the seal where the kick
start spindle exits the case cover. Check to make sure the spindle has a smooth polished
finish or it will ruin that new seal in no time.

I'm not sure what the official cutoff is for vintage. Personally, I figure anything you can't
find parts for anymore, qualifies.

dogger

_________________
1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R

I believe AHRMA calls VINTAGE MX 1974 and older, and POST- VINTAGE MX is naturally 1975 and up, with the longer travel bikes, but no disc brakes or up-side down forks. Now if I made a mistake here, you guys out there help us out on this subject. . .Please. It's been a while since I raced with the big dogs.

_________________
mikebike11y

63 Rickman Metisse
66 Triumph
66 Suz S32
66 Honda CB160s
69 Montesa Cappras
79 C&J Honda XR500
81 Honda 185S ATC
82 Suz GS650G
84 Honda Z50R
86 ATK 560
01 Kawasaki ZRX1200R
06 RCF450R "WOOD Dirt Tracker"
and a Sears lawnmower

The slipping is likely caused by wear in the kickgear components. There is a ring of teeth splined to the kick shaft and a mating ring of teeth on the kicker gear. These teeth have to mate together well enough to stay engaged while you kick it through. When you look at these teeth from the side, they are shaped kind of like the triangle section of this number 4. One ring of 4's is right side up, the mating ring of 4's is upside down. When you are kicking, the verticle edges of the 4 are up against each other holding tight to engage the kicker with the motor. When the kicker ratchets backward, the slanted edges of the pair of 4's are slipping right past each other allowing the kicker to return. When your verticle edges get worn, then the kicking direction begins acting a lot like the return direction and you get that nasty slipping you described.

If you've ever heard of back-cutting worn transmission gear engagement dogs to eliminate popping out of gear, you can do the same thing with your kicker gear ratchet. Take a small grinding wheel, like a dremel cut-off wheel, and evenly cut the vertical surface starting at the base of each ratchet tooth a little bit under vertical so that the teeth grab each other rather than slipping past each other. Do this with both sets of teeth - the set on the gear and those splined to the shaft. If you do a really small amount of grinding on these gears, you can get the ratchet mechanism work as good as new. Don't grind too much, just a wee bit.

I've done this on bikes when I had to, and have yet to cause myself any trouble.

Or, cut loose with the wallet and buy the two new parts if you can get them.

Enjoy,
Jon