Here are the pictures of the pistons,
DT on the left and the Ty on the right. Note that the corner of the skirt on the ty piston is slightly cut to clear the crankshaft.
Guy
TY250 E Piston
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Re: TY250 E Piston
Just picked up a Wossner catalouge this morning and they list the same piston for DT2/3, DT250, MX250 and TY250. I Guess they would have the corners cut away making them universial. If you got a DT piston it would be easy to trim of the corners to suit.
Incidently while I was at Serco I checked and they have the .5mm Wossners in stock.
Incidently while I was at Serco I checked and they have the .5mm Wossners in stock.
Re: TY250 E Piston
Hi Tricub & Guy
Thanks for the info I think I may be able to source a genuine TY/DT Piston. But still interested in the DT piston code.
I looked at MX250 pistons on Ebay the original pistons only have one ring and the skirt on quite a few look cut away more on the pin sides. So the aftermarket may suit but original???
Tricub thanks for the info on rebore I will try another rebore shop tomorrow. Its on the original bore so sould be OK square wise.
Cheers
Stan
Thanks for the info I think I may be able to source a genuine TY/DT Piston. But still interested in the DT piston code.
I looked at MX250 pistons on Ebay the original pistons only have one ring and the skirt on quite a few look cut away more on the pin sides. So the aftermarket may suit but original???
Tricub thanks for the info on rebore I will try another rebore shop tomorrow. Its on the original bore so sould be OK square wise.
Cheers
Stan
Re: TY250 E Piston
Hey Stanm be carefull in choosing MX, YZ or other high reving motor pistons, they don't have the same shape ( high reving motor tend to heat up ) they will be loose and you won't like the sound of your motor , plus I prefer a 2 rings piston.
Guy
Guy
Re: TY250 E Piston
Thanks guys for your comments. I got a original 0.25mm oversized piston from ebay and Phil at Dandenong Motorcycles said no problems to bore to that.
So some info on the A vs E model as promised. I am keen to know why they are so different in power
I have started with the piston and head
Pistons look the same and measure the same or close with measurements by vernia
I have an original E piston that weighed 288 gms and a 1.0 0/S A the weighed 311gm. So that about same for weight vs size.
I think the E and the A piston are the same
The Heads
I levelled the heads and added water and got the following
Both heads take 33ml . I measured to the plug and 1cm in and measurements close to the same so I think the same profile. I believe the E and the A head are the same.
If anyone can suggest a critical dimension i should check please advise.
I will investigate the Cylinder next and Post the results
Cheers
Stan
So some info on the A vs E model as promised. I am keen to know why they are so different in power
I have started with the piston and head
Pistons look the same and measure the same or close with measurements by vernia
I have an original E piston that weighed 288 gms and a 1.0 0/S A the weighed 311gm. So that about same for weight vs size.
I think the E and the A piston are the same
The Heads
I levelled the heads and added water and got the following
Both heads take 33ml . I measured to the plug and 1cm in and measurements close to the same so I think the same profile. I believe the E and the A head are the same.
If anyone can suggest a critical dimension i should check please advise.
I will investigate the Cylinder next and Post the results
Cheers
Stan
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Re: TY250 E Piston
Stan please compare the distance from the top of the exhaust port to the top of the cylinder. I'm thinking the E distance might be greater than the A.
Please also have a look and see if the conrods look different. I remember reading that one of the improvements that came with the B model was a lighter conrod compared with the A. I think this might be right too because my B and D motors have much less motor frequency vibration than the A.
Please also have a look and see if the conrods look different. I remember reading that one of the improvements that came with the B model was a lighter conrod compared with the A. I think this might be right too because my B and D motors have much less motor frequency vibration than the A.
relax, nothing is under control
Re: TY250 E Piston
Hi David
I measured up most dimensions on the A & E cylinder and taped off the transfer ports and measured their volume by filling with water. I have attached the scribble results. From results conclusion is from the outside they look different but inside they are quite similar. Will investigate the crank and crank case volume next.
Cheers
Stan
I measured up most dimensions on the A & E cylinder and taped off the transfer ports and measured their volume by filling with water. I have attached the scribble results. From results conclusion is from the outside they look different but inside they are quite similar. Will investigate the crank and crank case volume next.
Cheers
Stan
Re: TY250 E Piston
Hi David
Finally got around to checkingthe bottom end of the A vs E
I have both with the cylinder off at the moment.
Filled both cranks with petrol and got close to 490ml in both so not a great difference there.
Crank wieghts on E may be very slight ly thicker but only by 1mm.
Con rod on the A has markin of '311" and is 8mm thick
Con rod on the E has "498" marking and is 6.5mm thick
I got an original piston from Ebay and I believe it is a DT piston. It is almost 30gms heavier than the original Piston.
I will let you know how it goes.
Cheers
Stan
Finally got around to checkingthe bottom end of the A vs E
I have both with the cylinder off at the moment.
Filled both cranks with petrol and got close to 490ml in both so not a great difference there.
Crank wieghts on E may be very slight ly thicker but only by 1mm.
Con rod on the A has markin of '311" and is 8mm thick
Con rod on the E has "498" marking and is 6.5mm thick
I got an original piston from Ebay and I believe it is a DT piston. It is almost 30gms heavier than the original Piston.
I will let you know how it goes.
Cheers
Stan
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Re: TY250 E Piston
Stan I'm amazed that the port timing was so close between your TY250A and TY250E cylinders. I'm wondering if your A model is of a later type to mine. My A model has a very low ID number so I think it is an early one.
The first photo shows the front of the cylinder on my TY250A. Does your A cylinder have the flat round bit above the exhaust pipe like this one, or does it look like the cylinder in the second photo (which I think is an early B model cylinder) with the fins going all the way across the front?
David
The first photo shows the front of the cylinder on my TY250A. Does your A cylinder have the flat round bit above the exhaust pipe like this one, or does it look like the cylinder in the second photo (which I think is an early B model cylinder) with the fins going all the way across the front?
David
relax, nothing is under control
Re: TY250 E Piston
David, I have 2 434 cylinder and none of them as that flat round above the exhaust.
Guy
Guy
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