Planning on my next project.

[LaVern]

Hi All,  I several years ago I recondition my 1975 RL250 Exacta. I didn't get into the engine as it had always started 1st or 2nd kick and seemed to run just fine. Well it is getting noticeably tired and I believe my next project after I get my son's  1977 Yamaha TY250 done will be taking a closer look at the engine. Right now it still starts fine until it gets warmed up and then it not only starts hard but there is no low end whatso ever. I am thinking I definitely need at least to do a top end, bore, new piston and rings and crank seals. That's what I did on the TY without any problems, I figure that will be the least I have to do. I am the original and sole owner, and the engine has never been opened up.  My question is, can the crank shaft seals be replaced without splitting the cases like the Yamaha or do I need to split the cases? Never split cases before. I don't know if I would be getting in over my head if I had to. I do have a copy of the  Suzuki Service Manual and a bunch of factory service bulletins. Thanks 

LaVern

[djr]

It's a while since I rebuilt my silver engine beamish 250, but I seem to remember the right hand crankshaft seal being on the inside of the bearing ( with that bearing lubed by gearbox oil)

If my memory is correct, then splitting the cases is the only way to change the right hand seal

If I am wrong, I am sure someone will be along soon to say so

[LaVern]

djr,

Thanks for the reply. I am hoping you're wrong, but if you are correct, I will have to decide whether I want to tackle that or take it somewhere else. I guess I'lljust have to pull the side cover and take a peek.

LaVern

[diagnosis]

I was planning on doing the seals as well on my RL250, thinking it’s the same as the Yamaha, but unfortunately splitting the cases seems to be the only solution. 
You can see the seal (#17) behind the bearing in the diagram below. 
 

(sorry about the poor image quality, the size limit was only 80kb 🤷)

[LaVern]

I just found a picture of the Beamish Suzuki crankcase, and it seems to show the seals on the outside. I will try to post it, and see what you think,  if I am able to post it. It's a PDF.  Must be too large a file. I'll see if Ican work around that. Thanks for the response. Looks like I'll need to convert it to another file type. 

LaVern

[LaVern]

Let's try it again. I think the whole thing is there but it too is pretty small.

LaVern

[LaVern]

I don't know if they changed the RL250 engine that much when Beamish built them.

LaVern

[LaVern]

Diagnosis,

I guess I won't know until I take the side cover off. I won't be doing that for a few weeks at the soonest. I tried to convert the parts list but apparently I was allowed only one conversion frompdf to jpg. Anyway, the parts list says pts 17 and 28 are crankshaft seals and it shows them on the outside. I did not have this information when I first posted the question. I do see that the picture you posted seems to show at least one of them on the inside and one on the outside. Is that what you see?

LaVern

[djr]

Hello, I think the second picture is of the later "black engine" beamish 250/325, as this had a reed valve intake, as can be seen in picture.

The 1975 RL250 is a different engine, ( I think beamish called this the silver engine ?)

Unfortunately the picture showing the seal inside the bearing does match what I remember doing 

I think (could be wrong) the first silver engine is similar to the TM250 and maybe TS250 of the early 1970's, this would be in the first silver engine beamish bikes, the later 250/325 beamish engine was based on the later TS250ER reed valve  engine 

Edited September 30, 2023 by djr
Spelling

[LaVern]

djr,

That does make sense. I too remember hearing the RL250 was based on the TS250, and when I looked up the parts diagram I believe there is one seal inside and the other on the outside. So it looks like there is a good chance that a case splitting is in order. Thanks for the input. 

Lavern

[diagnosis]

Sorry for the late reply. I think I found the parts catalogue, where I found that image, on the Beamish Owners club website. It’s a great resource. I think on the Silver engine 74/75 exacta, it’s on the inside unfortunately.  I may tackle this over the winter, as the fall has been way too nice to put them away yet!

edit:  link to the main parts page;

https://www.beamishownersclub.com/parts-books

Link directly to the page I referenced;

https://www.beamishownersclub.com/_files/ugd/3a48b1_b4c5488ed747422d9c1fa79664e83f34.pdf

 

Edited October 3, 2023 by diagnosis

[LaVern]

Thanks for the reply. I too will have to wait on it. I have another project, a 1977 Yamaha TY250 I am restoring for my son, so I want to get a little further along on that, before I open another project. Mine has never been opened up so I am thinking I may need more than just a top end and new crank seals. That's what has me concerned. The closest I've come to splitting cases was back in 1970 when a '66 Husqvarna 360 I owned needed split and the guy I bought it from did it while I watched. My 72 year old memory recalls a bunch of spacers and bearings and gears. Whew, kind of scary at this point in my life. I gotta do a bit of research first. I will post on here anything regarding this when I get going on it. Take care.

LaVern