'Ello Peeps.

I know its not a trials bike but hope you dont mind.

My neighbour has just brought me his DT175 which had lost compression.

He has been lucky really. His piston rings disintegrated but it must have happened as the piston passed down accross the exhaust port as all the bits went into his exhaust. The bore is absolutely fine. I noticed that the piston is 0.25 oversize. Is this the first oversize?

It needs a top end gasket kit, Little end bearing (old one is fine but might as well) and a piston kit. He wants to go for a weiseco kit and i agree if the cost isnt that much different (I'll ring weiseco tomorow).

So where is the best place to get the gasket kit and get the price for a genuine yamaha piston kit?

Also, is this the same piston kit as for a TY175?

Does anyone have a manual for the DT175? If so what are the torque specs for the top end?

One last thing, Are these gaps in the back of the piston standard or are they some kind of upgrade the last time it was bored? (see picture)

Thanks for your help.

Marcus

Hi Marcus I too have a DT175 which has lost compression. So I went on ebay and found RD Parts Shop and on this page http://search.stores.ebay.co.uk/THE-RD-PAR...1167487QQsofpZ0

Steve.

Hi Marcus I too have a DT175 which has lost compression. So I went on ebay and found RD Parts Shop and on this page http://search.stores.ebay.co.uk/THE-RD-PAR...1167487QQsofpZ0

Steve.

Cheers steve. They have the piston kit in stock.

Was yours ok? What make are the pistons.

I dont suppose you have a manual do you? If so. could you look up a couple of things for me?

Did you try the dealer? They have a shocking amount of parts for the old stuff.

Cheers steve. They have the piston kit in stock.

Was yours ok? What make are the pistons.

I dont suppose you have a manual do you? If so. could you look up a couple of things for me?

It looks the same as the original and yes the holes in the piston are ports for gas exchange which I also have in my bike. I also have the manual somewhere which is for the twinshock and early monos but still is very handy as the engines changed so little.

Steve

It looks the same as the original and yes the holes in the piston are ports for gas exchange which I also have in my bike. I also have the manual somewhere which is for the twinshock and early monos but still is very handy as the engines changed so little.

Steve

Thanks Roxer.

If you can find the manual, could you tell me the torque settings for the barrel and head please? Also the piston ring end gap for a 0.25 oversize piston would be handy although that will probably come with the piston kit.

Also, could you tell me what the standard jetting is?

I just rang granby motors and they gave me a price of

Thanks Roxer.

If you can find the manual, could you tell me the torque settings for the barrel and head please? Also the piston ring end gap for a 0.25 oversize piston would be handy although that will probably come with the piston kit.

Also, could you tell me what the standard jetting is?

I just rang granby motors and they gave me a price of

be very careful with pattern pistons,some need much more bore clearance.

i have seen one seize up after a few minutes running,some seem to expand

far more than genuine pistons.