What's on your bench today?

[spudulike]

Many thanks Spud, from memory most of the old 2T bikes I worked on were open ported, I just remember the gaskets with holes for the side of the transfer ports but the good ones didn't breakdown so I didn't find out how designs had changed, also by luck I haven't needed to take the top any of my saws.

 

I assume a closed port engine could have a higher primary compression ratio?

 

I remember a Bultaco bike I had with a split window on the large exhast port, but this used to make a wear mark in the L section top ring loosing some compression.

 

I would say that the design and shape of the closed port lends itself to push new fuel vapour in to the combustion chamber and expel the exhaust gases, the twin port design allows for better control of the fuel vapour and stops fuel stacking in the transfers - the MS200 has a divider in the transfer port whereas the 020T doesn't.

 

The theory is that you are trying to push out the burnt exhaust gases with new fuel vapour and it is how efficiently you can do this. If you look at the top of the transfer and the shape of it, you will see why they are shaped and how they do this.

 

I don't know if it increases the primary compression but have recently read that the crank covers on the 357 were designed to do this giving it more power than the 359 so possibly true.

[Rich2484]

A 1989 trx350 Honda atv. Low compression so needs re boring with oversized piston as its that old Honda don't make parts for it anymore and I have to order from America.

 

Unless anyone knows an atv dealer in the uk that can sort some parts out for me.

 

Complete rebuild of the engine head and all. Been a pain in the backside as it sat in a farmers shed for 2 years then in a garden for another year, then it was ragged like stink and is now not working.

[GardenKit]

A 1989 trx350 Honda atv. Low compression so needs re boring with oversized piston as its that old Honda don't make parts for it anymore and I have to order from America.

 

Unless anyone knows an atv dealer in the uk that can sort some parts out for me.

 

Complete rebuild of the engine head and all. Been a pain in the backside as it sat in a farmers shed for 2 years then in a garden for another year, then it was ragged like stink and is now not working.

I hope your customer is going to pay ALL your hours you will spend on that one!

[Rich2484]

Damn straight. Told him not to bother and I would buy it off him for 300 as its knackerd, but he only paid 200 for it so he is happy to spend another 500 getting it fixed.

 

$130 for and oversized piston kit, but doeas come with full gasket set.

 

£50 for reboring by me.

 

Then it's all hours work after that, oh and fitting a road legal kit to it aswell. Should be next to the bench for a few weeks.

 

Keep me out the missis way for a while. Lol

[spudulike]

MS200t - bogging - compression measured and found the plug loose:001_rolleyes: 150psi, plug back in tight, bogging less but still a bit iffy....technical term that one:thumbup:

 

Will strip, clean, do all the normal checks for seal integrity etc, clean the carb and should see good use again.

[GardenKit]

Nice easy one today. Customer with MS181, said he had cut into some chicken wire and the saw stopped. He had cleaned out the wire really well but was annoyed that the chain would go round.

" please mend it" he said.

I said "ok"' i'll try.

Started the saw on 2nd pull, flipped off the chain brakeand hey presto, fixed.

One very embarassed customer. I wish i had done it after he left, I could have made up a story about a little bit of wire in the wrong place and saved his embarrassment. Plus I might have been able to charge him a tenner or two!

[spudulike]

Nice easy one today. Customer with MS181, said he had cut into some chicken wire and the saw stopped. He had cleaned out the wire really well but was annoyed that the chain would go round.

" please mend it" he said.

I said "ok"' i'll try.

Started the saw on 2nd pull, flipped off the chain brakeand hey presto, fixed.

One very embarassed customer. I wish i had done it after he left, I could have made up a story about a little bit of wire in the wrong place and saved his embarrassment. Plus I might have been able to charge him a tenner or two!

 

:sneaky2:Naughty Naughty:001_rolleyes:

 

Been cleaning up the poorly MS200T today - guess which part I have cleaned: -

[ecodao]

Hi GardenKit,

 

stories like that make you wonder if the people in question , should be allowed to use a saw ;-)

[Rich2484]

:sneaky2:Naughty Naughty:001_rolleyes:

 

Been cleaning up the poorly MS200T today - guess which part I have cleaned: -

 

Bet it was the flywheel.......

[GardenKit]

Had a customer in few days ago with an 039 with a loose exhaust and a missing nut. I pointed out that the exhaust was starting to break up and should be replaced, but he wanted it tightened and the missing nut replaced.

 

He came back today with the saw which had stopped suddenly and now would not pull over, it jammed just before TDC. I stripped it down to remove the bore ( what a pig of a job on the 039!)

 

Found a large piece of broken exhaust jammed into the top of the bore, stopping the piston. It had also done a lot of damage to the port edge of the piston crown whilst trying to get in!

Also bent the con rod.

 

I guess there must be a moral to this story:001_rolleyes: