Crank seals: OEM 14.8mm or DL NBR 15mm

Just looking for someone who has replaced the stock 14.8mm seals with better 15mm seals. I have dug through the forums but all I could find are people who replaced the other size seals with better aftermarket ones, a few who don't think 15's would work well and people who didn't say what size they replaced. I'm looking for someone who has actually has and there actual experience with replacing the 14.8's with better 15's.

I ask because for about the same price as the OEM 14.8 seals I can get double lip NBR 15's. I have 2 engines and want 4 sets but don't want to throw away money on something that might not work.

So if you have replaced the stock 14.8mm seals with 15mm seals please post how well they did or didn't work.

Lol one of those moments. Actually if I remember correctly I think you were one of the ones that thought 15's wouldn't seal around the shaft to well because of the .2mm difference. It might be remembering wrong though.

To clarify.
14.8x27x7.5 on the clutch side
14.8x27x3.8 on the magneto side

I want to replace them with double lip NBR's and the closest I can find are
15x27x7
15x27x5

Through hours of digging on these forums I found that there are 2 sizes of seals used on the china 2strokes. The size I have and the 17x29's. There are allot of people who replace the OEM seals with better ones but in all the post I found the only ones that stated what size are the ones that had the 17x29's. I could not find a single post that actually said they replaced the 14.8mm I.D. seals with 15mm I.D. seals.

I have an old engine on its last legs that has new seals but I messed up putting them in and am already getting an air leak and new engine that I had to take apart to clean out the machining grit they left in it and to replace bearing. One clutch and one crank bearing was very clunky and in the process I tore up one of the 2 seals.

So basicly I need 2 sets and everyone who has any charges $14 shipping even on the tiny seals. BGF is the only exception but he's out of stock and all the other vendors charge about $0.50 apiece less than the higher quality 15mm seals I found. I would just like to make sure they will work before I end up just ordering the OEM's.

multipaul confirmed what I assumed. Al has the same worry that I do, and no one has come in to say they have replaced the 14.8's with 15's, so it looks like I'm gona have to be a guinea pig. My new TV/Monitor might have to stay on layaway a bit longer if the 15's prove to be leaky. Now lets just hope the 15's work or my TV's bulbs don't decide to not come on at all. Right now I got to leave it on for a few minutes then unplug it and try again for them to light up, that or have it above 73 Fahrenheit in the room. I dread having to use the 19in monitor for a month but that's another story and off topic.

The motor that's gona get them first is near the end of its life without replacing the cylinder and crank so I'm not to worried about it. I'm just worried about wasting money. If they prove to seal good without a leak I'll put the second set in the new motor and start using it. Then I'll use the old motor to start building my Giant Stiletto that way if or when it decides to lock up it wont lock up my back tire at 30mph.

The "guinea pig" thing is a saying that's used over here when testing something. It's a rodent they use in laboratory tests of all kinds.

It wont be tell mid to late next week since its Friday and probably wont get shipped tell Monday.

The new seals showed up today but I didn't have time to put them in. I did get to test fit them on the crank of my new currently disassembled engine. It seems like they're gona work fine. It feels like they fit tighter on the shaft than the OEM one I have that didn't get tore up to get the bad bearing out of the new engine. Unlike the OEM seal I have, the spring doesn't try to pop out when trying to put it on the shaft, since the new ones are a harder denser rubber. So unless the distributor I ordered from sent me non NBR then I'm going to assume the OEM's are polyurethane.

I probably wont get a chance to install them tomorrow either. I'll update again after I get a chance to install and test them. Then we should have a thread to reassure people like me and Al that are skeptical about the .2mm difference. Since all the other posts about better seals either mention the other size or don't state what size at all.

I only put in the gear side seal as the magnet side showed no signs of leaking and I didn't see the point in replacing one that wasn't leaking yet. It seems to work so far but I sprung a headgasket leak and haven't had to time to fix it. Guess thats what I get for trying to reuse one without some copper coat. I have a new gasket and should have time today though.

Lapped the little grooves off the ring on the head and replaced the gasket. Took it about a mile or 2 at WOT and so far so good. I don't hardly ever take the bike on long runs so it'll take a wile to get a good mileage test on the seal.