gixxerjeff
Optimistic Underdog
This is indeed a momentum sucking bummer but I'm confident you will persevere. Hang in there, lean into it. 
-
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Honda RS125 - A Burnt Out Case...
- Thread starter Jung
- Start date
- Joined
- Apr 4, 2002
- Location
- Menlo Park, Ca.
- Moto(s)
- Keep me rocking life
- Name
- Budman
- BARF perks
- AMA Life Member #203453
A shop not being available and worse not return a call sucks ass. Lean on them.
Good luck.
Good luck.
bobl
Well-known member
I'm confused. The dial guage seems to indicate one hunderd and forty-four thousands. What am I missing? It seems to say "in" on the face. ?
Jung
Member
Thanks for the encouragement gents. The shop eventually did get in contact and I've sent it back. Fingers crossed.
@Bobl - the runout is the difference between the two readings. I didn't zero the gauge, hence the 140-144...it should be under a thou for a motor like this, ideally under half a thou!
I've made inroads in putting it back together with the old crank for now - it still looks in spec, so I suspect it should be fine for at least a day out. I've done a leakdown with new crank seals and it's ready to go back in the bike. It will be fun to fire it up at least, though I could have accomplished that with a carb clean!
A few pics...Both mastercylinders were beyond repair, note to self - don't leave brake fluid in bikes for longer than a couple of years! New Nissin 13mm front master cylinders are available but not cheap, and are also a road part, rather than the nice race casting that was on there.
I opted to treat myself and buy a Brembo RCS, which left me a bit skint for the rear. Amazon to the rescue, with the purchase of a magnificent, Chinese effort for $7! I ended up taking them both apart and making a hybrid. Don't use the rear brake on these anyway, so feel rather smart on the saving.
I also wanted to make a plinth of sorts to raise the seat, without cutting the frame. My poor old knees simply do not work in the stock format and lowering footpegs is not an option. A bit of ally box section I had lying around volunteered itself and half an hour with a hacksaw and the torch, I had something that worked. I'll probably go back to redo this - I'm so out of practice welding aluminum that I made a small hole. Not like you see it with the seat on though....
@Bobl - the runout is the difference between the two readings. I didn't zero the gauge, hence the 140-144...it should be under a thou for a motor like this, ideally under half a thou!
I've made inroads in putting it back together with the old crank for now - it still looks in spec, so I suspect it should be fine for at least a day out. I've done a leakdown with new crank seals and it's ready to go back in the bike. It will be fun to fire it up at least, though I could have accomplished that with a carb clean!
A few pics...Both mastercylinders were beyond repair, note to self - don't leave brake fluid in bikes for longer than a couple of years! New Nissin 13mm front master cylinders are available but not cheap, and are also a road part, rather than the nice race casting that was on there.
I opted to treat myself and buy a Brembo RCS, which left me a bit skint for the rear. Amazon to the rescue, with the purchase of a magnificent, Chinese effort for $7! I ended up taking them both apart and making a hybrid. Don't use the rear brake on these anyway, so feel rather smart on the saving.
I also wanted to make a plinth of sorts to raise the seat, without cutting the frame. My poor old knees simply do not work in the stock format and lowering footpegs is not an option. A bit of ally box section I had lying around volunteered itself and half an hour with a hacksaw and the torch, I had something that worked. I'll probably go back to redo this - I'm so out of practice welding aluminum that I made a small hole. Not like you see it with the seat on though....
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Jung
Member
I wish I could have taken a better picture of this - behold the VHM piston. This is without doubt, one of the prettiest parts I have ever put in a motorcycle. CNC machined from BILLET, in increments of 0.01mm. VHM really do an amazing job.
As mentioned, with new crank seals - I was a bit trepidatious about the leakdown test as the lands for the primary side seal had been badly butchered at some point. Fortunately, there appeared to be enough for the seal to sit nicely as it held a bit over 6psi for 20+ minutes with no change. My little home made tester cost about $15 bucks and is absolutely essential for any two stroke rebuild. I've even fired it across the shop a few times and it hasn't given up yet....
If it seems I'm rushing a bit at this point, I am! Having missed my date at Willow, I really need to get on with the RD250 to make sure that gets done in time for my next planned outing. Back to back failure to launch is not an option....
As mentioned, with new crank seals - I was a bit trepidatious about the leakdown test as the lands for the primary side seal had been badly butchered at some point. Fortunately, there appeared to be enough for the seal to sit nicely as it held a bit over 6psi for 20+ minutes with no change. My little home made tester cost about $15 bucks and is absolutely essential for any two stroke rebuild. I've even fired it across the shop a few times and it hasn't given up yet....
If it seems I'm rushing a bit at this point, I am! Having missed my date at Willow, I really need to get on with the RD250 to make sure that gets done in time for my next planned outing. Back to back failure to launch is not an option....
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bobl
Well-known member
Thanks for the explanation. I couldn't believe that someone could true a crank and miss by more than an eighth of an inch. Even the .004 is pretty damn poor. Hope it all comes together for you. Definitely a beautiful piston!
Jung
Member
Yeah .004 is miles out! Really not sure how they managed it.
The fit of the gudgeon pin in that piston got me way more excited than that sort of thing really should do.
The fit of the gudgeon pin in that piston got me way more excited than that sort of thing really should do.
Jung
Member
It's up and running on the old crank, I never found anyone that could help with the forks, so will give Solid Performance a bell - thanks!
Did you look into any CR125 crank options? I know the RS case was based on the CR. I believe there should be a CR125 crank option that would help you but I don’t know the year.