Going to try an engine tear down RD250

[oldguyRD1964]

Hi group, I'm not sure if the group shut down but something is different.
I've got an RD250 asked previously about the engine revving and the right crank seal is leaking.

So, I'm going to rebuild in a few weeks when I get back into town. I thought there were a few tools special tools I might need especially a large socket is the size 26 or 27mm? I bought a clutch basket tool, and I wondered if there is any other specialty tools.

I have a decent set of tools and maybe decent skills but I'm not going to lie, I'm a bit intimidated. Other than taking pictures and going slowly would anyone offer any additional advice?

Thanks

[m in sc]

just make sure you remove the 3 screw plate behind the clutch before splitting the cases. also, be very careful  not to lose any parts. lastly, i can not stress this enough,  try to get a hold of a #2 &#3 jis screw driver for the cross head screws  on the motor, they are not phillips.

[quocle603]

I've dont two splits before. Engine is really basic and simple. Just take your time. Record yourself and use zip lock bags to store/group things together. Like mark said, use the right tools for things. I followed a picture guide and used an impact gun to help take out those bolts and nuts

[SUPERTUNE]

Hi group, I'm not sure if the group shut down but something is different.
I've got an RD250 asked previously about the engine revving and the right crank seal is leaking.

So, I'm going to rebuild in a few weeks when I get back into town. I thought there were a few tools special tools I might need especially a large socket is the size 26 or 27mm? I bought a clutch basket tool, and I wondered if there is any other specialty tools.

I have a decent set of tools and maybe decent skills but I'm not going to lie, I'm a bit intimidated. Other than taking pictures and going slowly would anyone offer any additional advice?

Thanks

No worries here...never heard of a group that you speak of...
I'm a regular poster here and on the old forum, sorry if I missed your posts before.
RD's are simple, but for the first timer it can be a intimidating, as said from other posts.
I will also add, get a high quality impact driver and proper bits to remove very stubborn screws.
You can always PM/email me and I will always try and help keep you on the right track with your RD.

Chuck 'SUPERTUNE' Quenzler III

[oldguyRD1964]

Hi guys, thanks a lot for the tips, just three things:

1. JIS those are not phillips screw driver bits I bought some JIS bits with a t shaped holder but not sure so I'll take a look.

2. On the impact driver do you mean an air driven or hammer or electric. I own an old electric and a hammer impact driver, and a small compressor.

3. There is no need for a larger 26-27mm socket? I have up to 24mm....

Thanks, David

[m in sc]

hand impact driver.

i don't remember the socket sizes to be honest.

to be REAL  honest, ive been using a 6 point standards 1/2 inch drives for those nuts for 20 years, always worked for me. No, im not recommending it. 

[Redbird]

I'd never split open an RD either, and I guess technically I still haven't :P
But I took on reassembling an RD400 engine that was already split, with every part/nut/bolt dumped in a bucket. It seemed daunting. But as stated, these engines are really simple.
Take lots of pictures. Label parts in bags. And you can use a parts fische (BikeBandit.com has them online) to show you how 90% of it goes together.

And, there's a great group of people on here, and they're always will to help ;)

[Jspooner]

It's only as intimidating as you make it. They really are very simple. 95% of it will only go together one way anyway. I did my first one when I was about 16 with no help from anybody. The best advice I can give you is to make sure EVRYTHING is clean and don't force anything, if you have to force it it probably isn't right.

[oldguyRD1964]

Ok thanks very much, I'll be doing this in a few weeks... I'll write back with information!
thanks Dave

ps. I took a look and I have Motion Pro T-Handle Bit Driver with No. 1, 2 & 3 JIS They are .31mm not standard hex 1/4" so it will fit an impact and the T-handle...

I have an impact driver and I had a guy rebuild the engine's seals 6 years ago shame his work didn't last, that's the reason I'm going to give it a try... Did the site go down there were a lot of rebuild tips 6 months ago...

[SUPERTUNE]

Hammer Impact.
I have the snap on one, it works better than the chrome round ones it seems to me. I just use std #2 and #3 phillips with 3/8 socket , but you need to grind the tips of the bit to seat in farther to grab like a JIS type.
Chuck

[Evans Ward]

Besides the tag and bag method, take lots of pictures too as these will help with reassembly. I also like to take cardboard and sketch each cover on it and place my screws bolts through the template. Keeps things tidy and you will know where each screw/ bolt should go.  Parts fische like partzilla will help you too see how things fit. Get a factory service manual too for your year bike if you don't already have one.

[m in sc]

... Did the site go down there were a lot of rebuild tips 6 months ago...

sure did.. like 8-9 month ago and all the archives were lost. (its in the forum info section up top)

[Jspooner]

Me.......I don't bag and tag, never have. I throw all of the outside dirty stuff together and clean it together. Next I pull the clutch and and whatever else needs to be pulled from that side and all of that stuff goes into a 5 quart ice cream pail............they are the perfect size for holding that stuff, plus that means i get to eat ice cream so i can get the pails.  Next I remove the nuts and bolts holding the cases together and they all go in the bin with the "dirty outside stuff". Once the cases are split the trans gets pulled and set in an aluminum cake pan with a rag thrown over it. You will also need to pull the shift shaft so you can change that seal, other than that there is no reason the strip anything else from the cases, leave the shift drum and forks and all that stuff in there unless for some reason you need to change the bearing on the end of the shift drum...........pretty unlikely though. The main thing to remember when reassembling is to make sure everything is clean, old sealant removed, no burrs on mating surfaces, etc. and do not use silicone to seal the cases. When you drop the trans back in the main thing to watch for is that the shift forks are in the fork journals where they belong and not next to one. Before you seal it up set the top case half on and do a dry run thru the gears on the bench so you know it shifts. There's nothing worse than having to pull the motor back out because it doesn't shift. There are a few different things you can use for sealant, I like to use Permatex Anaerobic sealant between the case halves.     

[Czakky]

100% with you Spooner!

Having never been past the top end on a Yamaha 2t twin, but if I am too organized when rebuilding a bike it can feel too close to work for me....

[m in sc]

same here.