DT125R ARCHIVE

the only way is YAMAHA DTR · Guru

4DL00 zylinders?

fuggie · DTR Respected Member

i translated it and make it out to be that you exchange your barrel with scored nicacil for one they have replated and have in stock plus the ' 259.01'. Though you can get barrels replated in the uk for not too unreasonable a price just may take a few days longer as you have to wait on it getting done.

-- Edited by fuggie on Friday 9th of September 2011 11:43:47 PM

satelliteone · DTR Senior Member

4dl barrels are not plated, i have two here..3MB00 (P) but if ya can get one, they are ported better than stock. Used on the tzr125R 4DL, better still if and a big if is the the SP TZR125r HEAD BARREL. they are O ringed and ported to heck!.. 35HP with the reed block and carb, fit straight on a DTR bottom end.

I have been searching for the SP barrel/PV head, and piston for ages..no luck.

Dickhead · Nonce

next joke no road made has over 35 real hp

the only way is YAMAHA DTR · Guru

ye 32 if your luckey at the crank

satelliteone · DTR Senior Member

32 on the 4dl1 and the 4dlSP is 34hp.

race 125 GP bikes are up at 42HP

http://www.motorbikespecs.net/index.dyn?flag=2&model_id=2147687&make=Yamaha

do ya research! robin.

this GP 125 is a 150mph bike! 45HP.. so! thats NO joke!

http://www.youtube.com/watch?v=2l8taqD4f8U

fuggie · DTR Respected Member

only saying they were coated because thats what the advert suggests, 3mb barrels are ten a penny, pretty much a stock item i thought and not that different from the basic origional 3bn barrels though with some basic extra curved edges on the transfer ports but still with the cast in transfer restriction, the sp is a different kettle of fish as you say with the exhaust boost ports and full length tz style scavange (doesn't look promising for skirt life) and 4fu with tidy unrestricted casting, nicacil and muli taper squish band with a tapered edge piston to suit.
i know with the 250 varient of the engine to even begin getting anywhere close to the power your describing per cylinder you would also require 'kit' spannie ($fortune$) and yamaha supplyed additional tuning suppliaments for powervalve, squishband carb modification and port map which would also bit used with racing 'kit' parts for example revised cdi for ignition timing and powervalve control timing, all super expensive elusive parts and this is a production racing tune not gp so still down on power. It still takes more work than that to get a tzr 250 to 70hp at the rear using different carbs, tz pipes etc.

Dingle001 · DTR Senior Member

and if you did all that work expect to change a piston every 500 miles and a crank every couple of thousand!!

satelliteone · DTR Senior Member

going back to the 4DL2 SP barrels, they might have been coated, it says fresh coated!.. wonder why?. i dont really know. but power from a 4DL2 is stated above 30HP. a 32MM dellorto as standard., the 3MB00 heads are different has a "P" marker on the 4DL1. why state that a 4DL1/2 has 30+HP in all docs?.. when u guy believe other wise. that was the figures from motori Minarelli, belgarda! not yamaha, The Jap version was 28HP. The RS is that de-restricted, and KTM use the 125 EXEC full power. they all seem to last well...

and i do agree, a 45HP GP machine, will need rebuilding after each race. thats pretty understandable.

the SP barrel is one hard piece to find, along with the PV, piston, and even the 2 piece gasket.

fuggie · DTR Respected Member

its probably still a measurement off the crank, some manufacturers do that, like triumphs figures can look quite impressive next to jap bikes but they measure off the crank rather than the wheel! though the japs tend to pick a number out of thin air lol, as to the sp barrel you can do a similar port and if you get a piston with the correct transfer cutout there is enough meat on the barrel at that point to hog it out so the transfer extends right across, i've done that with the barrel i'm about to use, the only downside is you don't get the boost ports for the exhaust (though someone on here did put their own in!)

http://www.essexbikers.co.uk/forum/showthread.php?1341-my-tzr125-(2RK)-on-the-dyno

the only way is YAMAHA DTR · Guru

all the cylinders for the belgarda http://www.geiwiz.de/search_result.php?catid=1013&children=1013_246_262_287_283_289_1352_1358_1359_1355

rob patton · DTR Respected Member

show me a 125 road bike with 35hp + then

satelliteone · DTR Senior Member

"show me a 125 road bike with 35hp + then"

there ya go thats on a brittish road with MOT and tax

http://www.youtube.com/watch?v=2l8taqD4f8U

Ahhh or did u mean a UK spec learner legal? than ya stuffed!