Two quick engine rebuild questions

[jayman87]

Does anyone know how to remove the circlip on the end of the shift drum.


(I'll upload the pic again if it's need after the server move)

I've been fiddling with if for a while and was wondering if there was a special trick to removing it. I'm about at that point where I drill it, break it, and order a new one, but I'd like to avoid that.

Also I was wondering if there was an alternative to using Kawabond, hondabond, or whatever $50+ liquid gasket to seal the crankcase with. It seems odd that we need this expensive stuff compared to what a car might use for 7 bucks.

Permatex Ultra Black® Maximum Oil Resistance RTV Silicone Gasket Maker

I'll admit I'm trying to pinch a penny, but if I need it, I'll get it.
If the kawabond is what we need for the job, why? If not what else can we use? Has anyone had success with other liquid gaskets?

[supahtim]

Tru arc pliers to remove the circlip, no idea about the other stuff.

[jayman87]

Thanks. I'll be sure to get a set the next time I do this. For now I managed to figure it out. After trying different ideas and tools, I managed to get some thread in the loop and pop it off. The needle nose pliers that couldn't get the clip off, worked great for getting it back on.

[alex.s]

circlip pliers are slightly bent out at the tip so they grip the circlip so you can extract it. i usually just use a knife

[jayman87]

I wasn't gonna bother updating but figured I'd be good to have it here if someone searches for liquid gasket later.

I took and cylinders and pistons to a dealer nearby to get them checked out and honed. When I went to pick them up. I asked him is it really necessary to use Kawabond or hondabond when sealing the crankcase. I was thinking he was a dealer mechanic and I might get a bias answer cause he wants me to buy it here. Instead he says "as long as it's oil resistant, like Ultra Black, I've used that before." Then he reminded me not to actually put a bead of it down when I used it, and I told him a put a dab on my finger tip and smear a thin layer and even that was a little too much.

So if you want to do it right get the Kawabond. If you want to do it cheap but effective, Ultra Black

If I have any leaks or problems or whatever later I'll update the the thread.

[alex.s]

so what was the problem with the engine anyway?

[jayman87]

Here's the short version. Originally, the cam chain stretched and it was rattling pretty bad. I opted to replace just the chain instead of swapping engines. I took a short cut and left the top end of the engine intact and only took off what I had to, to remove the bottom half of the crankcase. Blah Blah Blah I'm an Idiot, the lower chain guide ended up broken. Also one of the generator cover screws broke off in the crankcase while I was taking the cover off. That's not a big problem until your break the screw extractor in the hole you drilled in the broken screw. I can give further explanation if you like, but it's easier if you just accept that I'm an Idiot and move on.

So now my though was to just buy a new bottom half of the crankcase since both problems where on that one piece. The mechanic that later honed the cylinders for me, advised me not to. I don't remember his explanation anymore it was months ago, something about how they were made. Now I'm replacing both halves of the crankcase and moving everything from one to the other.

Though this has been a pain in the ass it was worth what I learned. I'm gonna try and get a job at a bike shop. I hear people start out like that all the time. Perhaps I should get this thing running before I apply.

[alex.s]

Originally Posted by jayman87

something about how they were made.

the clearance between the case bearings and the crank itself need to be very precise and you would need to plastigauge the current case/bearings/crank combination in order to know what size bearings to put in to be within the cranks clearance limits. if you don't do this the crank just eats through the bearings and you wind up with thrown crank bearings.

[jayman87]

Well.....**** ( LOL )

That's the pain in the ass part of this. There's always something. I'm glad we had this chat now before I put the crankcase back together. I'll look up how the plastiguage works. Does it make any difference that I also swapped all the bearing from my old case as well? I'm betting no.

[alex.s]

it will still be off. and i hate to tell you this but the crank bearings are going to set you back about another $150 for all of them in the right sizes. assuming you get it right the first time.

[alex.s]

note if you just need a running engine for a day or something... the crank should last at least 500 miles or so with incorrect bearings... might even go as far as 1000 miles depending on how far off the bearings actually are....... just something to think about. its always best to get crank/rod/case/bearing combinations from a single engine since they are correctly sized to each other. heads, cylinders, pistons, transmissions, that crap doesn't matter since the clearances are pretty massive comparatively.

[jayman87]

I just want my baby ninja back, complete with baby cam chain rattle.

This what I'm gonna do. I just ordered the piston rings, circlips, and cylinder head and base gaskets, so I got time to get and play with the plastigage while they ship. If it doesn't check out (let's face it, it won't), I'm gonna ride this thing til it dies then do an engine swap.

[thejaredhuang]

http://www.harborfreight.com/snap-ri...eads-3316.html

[jayman87]

Update

It may not be that bad. I can see what you mean when you say if I get it right the first time though. If I did this right I think I only have to replace one bearing (2 halves). The rest should match up. I recorded a vid on my phone explaining how I came to this but I want to edit it before I upload. And I bought some plastigage. I'll do all this tomorrow.

[jayman87]

Plastigage confirms it, I just need to replace the one bearing. If it doesn't work out you'll probably hear from me in about

Originally Posted by alex.s

at least 500 miles or so with incorrect bearings... might even go as far as 1000 miles

Thanks for the info, if I got this right you just save me a lot of grief and money. I'm gonna read through the service manual again to make sure I understand this correctly.

[alex.s]

i just wish someone had told me that before i replaced my first crank... would have saved that engine. oh well. pay it forward

[n4mwd]

Wow, such fun.

Case sealant: Don't use permatex, use Hondabond HT. Its about $15 at the local Honda car dealer.

Mixing case halves: Don't do it. They are match machined as a pair.

New case: There are marks on the case that tell you what kind of bearings you need. If the case markings are the same as the original, then you can use the same bearings.

Bearings: Use plasigauge on the case bearings. As long as you didn't remove the rods from the crank, you don't have to do anything there. If the bearings are in spec, then you can reuse them. They are about $10 per half and most dealers wont take them back if you get the wrong sizes. It will also be handy to have a micrometer that can measure down to the micron size because that's how high the tolerance is on these engines.

Throw away parts: If you mess with them, you need to replace rod bolts and nuts, wrist pin circlips, and clutch basket nut.