DBP on 760 / 62T
- Thread starter sturat
- Start date
blasterdude
Waiting for the ice to thaw!!!!
- Location
- The Region
DBP is Dallas Baker Products which was part of Pro-Tec. Not sure what the numbers mean though
So could this be a ported cylinder or perhaps and ported engine
- Location
- Rochester, NY
You could call pro-tec. My experience is that they are super helpful
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
PT80 probably means it is bored to 80mm Stock 701 Bore is 81mm. So I would say yours is a 650 Big Bore. But Just throwing darts at this.
- Location
- Canberra, Australia.
See that colour on 650’s all the time. 701’s are typically black or silver.
It might be worth looking down the spark plug hole and seeing if there’s any numbering on the piston crown (some manufacturers machine/engrave part numbers on there that can be used to determine the piston size). Or pop the head for a peek if you don’t mind the cost of a head gasket.
It might be worth looking down the spark plug hole and seeing if there’s any numbering on the piston crown (some manufacturers machine/engrave part numbers on there that can be used to determine the piston size). Or pop the head for a peek if you don’t mind the cost of a head gasket.
You guys know more than I do... I've had a few Yamahas and don't know the ins and outs, mainly a Kawi guy. I'm gonna call pro-tec today. My intent was to throw this into my square nose but I have been considering a jetmaniac build as well.
I called and confirmed this is a Dallas baker products 61x/62T setup built back in the mid 90s based off the numbers I provided. With the head and dual 44s on there, and given the green color of the cylinder, it was assembled piece by piece and was heavily ported... looks like I've got a great setup for my square nose.
VXSXH20
Sionis Industries
- Location
- Mid-Atlantic
take a look at the exhaust port. I'd bet that has a very distinct wide profile on it .
81mm bore. It appears to be a stroker. Do I just measure how much comes of the piston comes out of the sleeve heightwise in mm?
I plan on busting it down next week to rework and then I'll get what I need powder coated when my b pipe comes in. No big nicks or scoring, I think one step up should do it.
I plan on busting it down next week to rework and then I'll get what I need powder coated when my b pipe comes in. No big nicks or scoring, I think one step up should do it.
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Gonna say that is on old race engine. They use to take the 650 and Big Bore it and Stroke them. Made good power.
I found 61x on the cylinder. My eyes are not as good as they used to be. Would the 650 cylinder still be stamped 61x?
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
61x should be a 701. But the damn heads have all different numbers!!!! Cannot tell you on measuring stroke, post a pic of the head, Gonna guess the domes are stepped to allow for proper clearance of the pistons/squish.
waxhead
wannabe backflipper
- Location
- gold coast
can you give the height to the top of the exhaust port and the top of the transfer. also the piston protrusion and I will run some calcs for you
bored&stroked
Urban redneck
- Location
- AZ
porting channels? Never seen that before. Cool.
- Location
- Riverside, CA
According to Dallas, that style of porting was developed by Rick Burgett
"Lumberjack" A factory Yamaha MX team rider in the late 70's. Dan used
that port layout on the 93' World Tour XIr's, but I don't think it was used
in the 94' XIr's.
That exhaust port appears to be more aggressive than his early engines.
Dan's 93' engines had a hump in the top middle of the port, which was
a characteristic of Dallas's earlier engines. The hump was to promote an
earlier bdt, and still maintain the torque of a lower bdt engine.
Bill M.
Dan did a magazine article with one of the magazines after the 93' WF's,
where he shared the engine details (but no specs??). The picture was taken
outside the R&D double doors. I think that is as close as they got to the
PJS R&D.
"Lumberjack" A factory Yamaha MX team rider in the late 70's. Dan used
that port layout on the 93' World Tour XIr's, but I don't think it was used
in the 94' XIr's.
That exhaust port appears to be more aggressive than his early engines.
Dan's 93' engines had a hump in the top middle of the port, which was
a characteristic of Dallas's earlier engines. The hump was to promote an
earlier bdt, and still maintain the torque of a lower bdt engine.
Bill M.
Dan did a magazine article with one of the magazines after the 93' WF's,
where he shared the engine details (but no specs??). The picture was taken
outside the R&D double doors. I think that is as close as they got to the
PJS R&D.
Last edited:
waxhead
wannabe backflipper
- Location
- gold coast
he just sent me the measurements of the ports
exhaust 36.5
transfers 52.5
on a stock stroker assuming this was machined and this is why the pistons are hanging out the top
ex 180 and transfers 121 transfers
on a 5mm stroker you are at
190.7 ex and 138.4 transfers
sorry mate I think the cylinder is trash going off those numbers.
It will run no doubt about it but not anywhere like it should.
if you fit stock stroke crank assuming this one is a stroker in there now you get
186ex and 132 transfers.
some one has simply lifter those transfer to the sky and you are going to be severely blowdown T/A limited
exhaust 36.5
transfers 52.5
on a stock stroker assuming this was machined and this is why the pistons are hanging out the top
ex 180 and transfers 121 transfers
on a 5mm stroker you are at
190.7 ex and 138.4 transfers
sorry mate I think the cylinder is trash going off those numbers.
It will run no doubt about it but not anywhere like it should.
if you fit stock stroke crank assuming this one is a stroker in there now you get
186ex and 132 transfers.
some one has simply lifter those transfer to the sky and you are going to be severely blowdown T/A limited
- Location
- Riverside, CA
Dallas is a better engine builder than a ~25' BDT.
Perhaps the measurements didn't include the new piston height?
Bill M.
Perhaps the measurements didn't include the new piston height?
Bill M.