Over the holidays I purchased a '87 CR80 that needed a new crank and bearings so I went through the motor, used the all-balls crank bearings and seals and freshened up the top end. Well upon firing it up, it smoked alot and frequently fouled plugs but ran great inbetween. I checked the gear oil and it was low. So I know that oil is leaking past the right crank seal or the crankcase gasket- I sure hope its just the seal. How often does a crankcase gasket leak? I made extra sure to get both mating surfaces clean, but I did notice a few hairline nicks in the mating surfaces. I was told that the crankcase gasket will expand when oil touches it. I just got new crank seals and a complete gasket kit. Any tips would be appreciated. I wonder if I should use a spray on sealant on the gasket this time around to assist its sealing capabilities.
1987 CR80 losing Gear Oil
- Thread starter bryank30
- Start date
You may have accidentally snagged the crank seal while reassembling. Be very careful when mating the crankcase halves so you don't knock the gasket out of place.
I had one of those bikes when I was in high school. I was a fair bit too big for it, but it ripped. I bought mine, in need of a top end, for 100 bucks. It was the best smile per dollar bike i've ever owned. It would flip over in top gear with my tall skinny arse on it. I gave several people a good laugh with that little death trap, lol.
I had one of those bikes when I was in high school. I was a fair bit too big for it, but it ripped. I bought mine, in need of a top end, for 100 bucks. It was the best smile per dollar bike i've ever owned. It would flip over in top gear with my tall skinny arse on it. I gave several people a good laugh with that little death trap, lol.
- Thread starter
- #3
Yeah its fast. I have been getting parts off of ebay for it. I got a factory expansion chamber that is perfect for 15 dollars on ebay. Alot of Dupont Imron II on the painted surfaces and hunting here and there on ebay and I am bringing this one back to its full potential. I did a little work on the exhaust port with my die grinder and a 1/2'' sanding roll and richened the main jet 2 sizes. I almost would bet it could give a CR85 a run for its money.
