Yamaha SR500 Resurrection - help!

[Helen]

Hi

I'm trying to reconstruct my SR500 which is in a zillion pieces. The bike was my only form of transport some 20 years ago and was taken off the road as the little end was worn oval. I stripped it all down ready to sort out about 15 years ago and it's been in boxes ever since!

I have a couple of things I need help/advice on to get started if anyone has any ideas please (any there will probably be loads more questions to come!)

1. Should I try and get hold of a new conrod and get the crank split and replace it? If so, where can I get one from? Are these still available somehow or am I being a bit optimistic here?

2. Is it possible to just get the conrod bored out and have a sleeve put in it?

3. My front wheel and mudguard have disappeared somewhere along the way. Can anyone recommend a breakers that deals with old stuff like this? I live in Notts, but I don't mind travelling a way if necessary.

4. The seat needs re-covering (and a bit taken out of the front as I've only got little legs and my original seat with a bit taken out has also gone astray).

Thanks

[boze]

Hi

I'm trying to reconstruct my SR500 which is in a zillion pieces. The bike was my only form of transport some 20 years ago and was taken off the road as the little end was worn oval. I stripped it all down ready to sort out about 15 years ago and it's been in boxes ever since!

I have a couple of things I need help/advice on to get started if anyone has any ideas please (any there will probably be loads more questions to come!)

1. Should I try and get hold of a new conrod and get the crank split and replace it? If so, where can I get one from? Are these still available somehow or am I being a bit optimistic here?

2. Is it possible to just get the conrod bored out and have a sleeve put in it?

3. My front wheel and mudguard have disappeared somewhere along the way. Can anyone recommend a breakers that deals with old stuff like this? I live in Notts, but I don't mind travelling a way if necessary.

4. The seat needs re-covering (and a bit taken out of the front as I've only got little legs and my original seat with a bit taken out has also gone astray).

Thanks

hey, glad to hear ya wanna get her running!

i always order parts from the yamaha dealership in glasgow, im not sure if they can deliver but they do pretty much everything for every yamaha ever built!

theyre called "ride on" try giving them a buzz on 0141 423 2773 and see if you can get a new conrod.

ebay is a good place to look for mudguard etc also check out the links at the bottom of this page: http://www.motorcycle.co.uk/lists/PartsClassic.html

peace

Damo

[guest27]

Hi Helen

Welcome.  Sorry I cannot help with the questions, just wanted to say Hi and welcome to our happy band.  As to the conrod I would be inclined to seek out a replacement - either Yamaha or a pattern part if available - rather than get the one you have bored and bushed.

Are you looking to build a perfect SR500 - except for the cut down seat - or are you happy to mix and match - it may be that the front wheel / front end from another Yamaha will do a good job and be more available - I do nto know but I bet someone here does.

R

Look forward to seeing pics

[Helen]

Hello!

Thanks for your replies - the bike doesn't need to be original. As long as the front wheel looks reasonably similar to the back one that'll be ok.

Helen

[guest7]

I had an NX650 conrod bushed some years ago (due to a blow up - it had 'picked up') and the repair is still performing its function perfectly.

What was the better, the engineer did it with the crank still in place in the cases.

Cheers
GC

[Helen]

That's interesting - I'd assumed it the crank would have to be spilt for the conrod to be machined. Was it expensive? I have been quoted about £100 for a new conrod (thanks for the phone number Damo!) then it would have to be fitted to the crank as well....

Helen

[Steve H]

As Graham says it possible to have the little end bushed, and some engineers will do it without stripping the engine. I rememeber a conversation years ago with a machinist who was explaining how he machined the littles ends in situ, I scratched my head for a while and asked about all the swarf generated. Aha he said very I have a very special tool made by tesco's, and he pulled out a plastic bag. Obvious really.
As for the wheel you may find XS650 parts fit, a common conversion is to use an XS650 front end to get a twin disc setup

[guest27]

Well that told me...

That is the good thing about the peeps on here - never worried about helping a guys education.  So ignore all I suggested and seek out an engineer to re bush the eye with the crank in situ - sounds like a much better outcome to me.

R

[Helen]

Hmmm.... yes, now I'm really beginning to wish I hadn't removed the crank from the engine all those years ago...

[MrFluffy]

I have to add if the ovality is really bad and you take a lot of material out to correct it, it goes without saying that you risk weakening the conrod in the little end area which can have naughty concequences. But thats for the engineer that does the job to assess/decide if its viable...

[peterj]

Any reduction in strength from bushing could be more than compensated for by a small lowering of the redline. My memory of SR's tells me that chasing the redline wasn't a very enjoyable experience anyway. You aren't looking to build the ultimate performance SR are you?

[Ken]

If its oval you have to be quiet carefull that you find the original centre before you bore it out. I dint know for sure but you would expect a conrod to be made of quiet hard material and so had to work on . Maybe you could  have it honed out along with the piston and fit a slightly larger gudgeon pin.

Just a thought

Ken

[Helen]

Hi Ken

Looking at the gudgeon pin, it's only showing wear marks on one half (it's slightly burred) so I'm assuming that the wear in the conrod is also just on one side, so maybe not too hard to find the original centre?

PS Please excuse any mechanical/terminology gaffs I'm making here guys - it's ages since I've looked inside an engine!

[guest27]

Use the correct technical terms and no one will know what you are going on about - well the sad few will.  Describe what you see and the rest of us will think - Ahh I know that.

"Thingy" - the correct technical term for any part for which you are unsure of the function.
"Widget" - a complex looking "Thingy"
"Sticky out bit" - and "Thingy" that sticks out.
"Sticky in bit" - any "Thingy" that sticks in.

Not to be confused with a "Bit Sticky Thingy" - this is any bike part handled by a 4 year old who has been eating sweets.

"Fettle" - to take apart and rebuild in the hope that it will now work better.
"Buggered" - any mechanical device Roger has "Fettled"
"Mullered" - any mechanical device Roger has tried to repair.

R

[guest7]

The very first TC newsletter had a glossary of biking terms. My favourite was:

Sidestand - a device for poking deep holes in soft ground.

GC