racerd

you could put a rd engine into your dt or you could put the complete top end of a rd on, ?have you tried e bay

do you mean the crank moves side ways in the main bearings if you do then the crank journals are worn also what colour is the firing tip on the spark plug

http://rdcchatforum.forumcircle.com/index.php

would the r6 parts fit onto your fazer

QUOTE (yamafun @ Dec 30 2006, 08:26 AM) * MY 1979 YAMAHA DT175 HAS 22 HORSEPOWER AT 12000 RPM. MAX RPM IS 13000RPM. DYNO TESTED USING A DYNOJET 2 WHEEL AUTOMOTIVE DYNO. USED ONLY ONE ROLLER INSTEAD OF BOTH. ORIGINAL HORSEPOWER WAS APPROX 14 HP AT THE WHEEL AT 7000 RPM. MODIFICATIONS ARE THE FOLLOWING: IT175 CYLINDERHEAD MODIFIED ON A LATHE; SHAVED CYLINDERHEAD BUT MADE COMBUSTION CHAMBER WIDER. OCTANE USED 91 OCTANE. USED 1977 IT175 CARBURATOR MODIFIED; BORED OUT TO REDUCE VENTURIS. REJETTED ON THE STREET FOR THROTTLE MAX AND FULL THROTTLE; MAIN AND IDLE JETS. K&N AIR FILTER. STOCK CYLINDERHEAD BORED TO FIRST OVER, PORTED TO SPECS OF 1977 IT175 PORTS SIZE. EXPANSION CHAMBER FROM 1991 HONDA CR125 MODIFIED TO FIT. MUFFLER PROCIRCUIT FROM 1991 HONDA CR125 MODIFIED TO FIT. 4TH GEAR WILL HIT APROX 80 MPH. HAVE NOT TRIED 5TH AND 6TH GEAR. BIKE IS TOO LIGHT FOR THOSE HIGHER SPEEDS. DO NOT TRUST BRAKES FOR THOSE SPEEDS. NEED TO UPGRADE FRONT DRUMS TO DUAL PISTON DISC BRAKES. 12000 RPM. MAX RPM IS 13000RPM. this is for the race track on the road 11,000/11,500 spot on, STOCK CYLINDERHEAD BORED TO FIRST OVER = IT175 CYLINDERHEAD MODIFIED ON A LATHE. at what angle was the squish re cut to and did you measure the squish also this lines up the edge to the cylinder bore, CARBURATOR MODIFIED; BORED OUT TO REDUCE VENTURIS. what size is the carb now, REJETTED ON THE STREET FOR THROTTLE MAX AND FULL THROTTLE; are both the same meaning, wot = wide open throttle, K&N AIR FILTER. have you oiled the filter also you need the reed block porting and flowing and finishing off in 80 grit production hone marks this aids the mixing of the fuel and oil into the engine taper port the front of the carb open out reed stops inlet port open 360 degree reed block stops and starts flow exhaust port 22mm from top of cylinder liner and make the exhaust port wider as well guide inlet flow towards boost port line up transfer entrances on the barrel to crank cases the ports need a 2mm chamfer at a 10 /12 degree angle flat and polish piston crown and combustion chamber in cylinder head and the exhaust port bigger carb if not using a boost bottle then connect one set squish to 1.00mm

12000 RPM. MAX RPM IS 13000RPM. this is for the race track on the road 11,000/11,500 spot on, STOCK CYLINDERHEAD BORED TO FIRST OVER = IT175 CYLINDERHEAD MODIFIED ON A LATHE. at what angle was the squish re cut to and did you measure the squish also this lines up the edge to the cylinder bore, CARBURATOR MODIFIED; BORED OUT TO REDUCE VENTURIS. what size is the carb now, REJETTED ON THE STREET FOR THROTTLE MAX AND FULL THROTTLE; are both the same meaning, wot = wide open throttle, K&N AIR FILTER. have you oiled the filter also you need the reed block porting and flowing and finishing off in 80 grit production hone marks this aids the mixing of the fuel and oil into the engine taper port the front of the carb open out reed stops inlet port open 360 degree reed block stops and starts flow exhaust port 22mm from top of cylinder liner and make the exhaust port wider as well guide inlet flow towards boost port line up transfer entrances on the barrel to crank cases the ports need a 2mm chamfer at a 10 /12 degree angle flat and polish piston crown and combustion chamber in cylinder head and the exhaust port bigger carb if not using a boost bottle then connect one set squish to 1.00mm

un bolt it from the frame, if you are using cone filter you might need to use a spacer tube and remember to check jetting so the engine does not run lean = holed pistons, what other mods as your dt got

start at the air box is there a intake snorkel on the airbox if so remove it and make the hole that you see bigger and you could even drill holes in the top part above the air filter or even use a cone filter or a foam filter, also you could change the carb for a slightly bigger one and ream out the inlet manifold to the inlet manifold gasket and even the inlet port to the inlet manifold gasket, racing spark plug, performance exhaust, up the compression

when you have re installed the crank, you need a feeler gauge to centre the fly wheel crank webs in the crank cases, also you could try putting one half of the crank case in the oven and the main bearing in the freezer for the same time for 30 minutes, this applies to both crank cases this is to expand the crank case so the main bearing goes in and the main bearing in the freezer contracts the main bearing and this is the same method for installing the crank in to the crank cases but then you put the crank case in the oven which already has the main bearing in then put the crank in the freezer

in the photo below shows the rubber o ring this must be put back on and a touch oil smeared on the rubber o ring have loads of photos on a assembly of a vm round slide carb on my forum

Do Not De restrict the Bike!! I Did And It Went Bang, how would De restricting the engine make it go bang, have you tried De restricting the air box and have you tried a foam air filter or a cone filter if you do this then you might need to up jet the carb to stop the engine running lean, you could try a different exhaust,

yes i do want to know what was he like

yeh make sure the old oilfeed pipe [from pump ] is blanked off properly . & when running in [rebored] make the twostoke mix alittle richer .[ plenty lube] say 30/1 or 25/1 ........ why would you need to run 30 to 1 or 25 to 1 when running in to much oil ratio and the motor will not run in right but this depends on the make of 2 stroke oil being used run my motor in at 50 to 1

but open it up and she just dies, go back to go back to part throttle and she picks up again. . might need a bigger main or might need a smaller main jet, a plug chop is need to sort this you need to run it in first 500 to 750 miles no more than half throttle, also you need to do a plug chop, when running premix run at no less than 50 to 1

need to grease up the linkages and swing arm spindle this means taking out the swing arm

you could try using a ram air filter and a spacer tube, also a bigger carb,open out the reed stops, port and flow reed block, port the barrel, line up transfer entrances to crank case mouth, set the squish to just under 1.0 mm, flat and polish piston crown/combustion chamber/ exhaust port, use a couple of base gaskets, racing spark plug and plug cap, ledar air corrector kit

this called entrapment

if the manifold sucks in air this will cause lean running and holed piston crowns

fibre reed should be ok but these work with other mods done to the engine as well

if you have a k and n filter you might need a spacer tube that goes on the back of the carb, a ram air filter might be better, to find out what size main jet you need you have to do a plug chop to see the colour of the burn, what size main jet are you running

when I shift in the fifth gear at gaining full speed the bike loses power and the rpm keeps falling is the gearing to high, like no spark is the ht coil dead

just peg open the power valve

or it could be the pilot jet to big

yes it is the water pump oil seal what happens is when the seal goes the coolant goes into the gear box

ihave a dt mx ,i have raised the top of the exaust port ...all is ok, a bit more mid boost..i have a gianeli exhaust ,trying to get a bit more pwer out of the engine,,,i have been told i could advance the timing when you raised the exhaust port did you chamfer the edge this is to help the piston rings go over the port if you did not chamfer the edge of the port this could break the piston rings and wear them out faster, if you want more power then try looking at bigger carb, open out the reed stops, change reeds, port and flow reed block set the squish up to just under 1.0 mm, port the inlet port, match up transfer entrances to crank cases, if you advance the timing too much this causes detonation holed pistons and makes the engine run slower, also when tuning you need to do a plug chop to see how the mixture is burning in the cylinder if you run lean then you get power fade then a nip up and or seize up and holed pistons, you could try using a racing spark plug and plug cap