200x cam tuning?

[hippyplz]

I have a 84 200x that i put a wiseco piston and a ported head a cup months back and everything was fine. Then over the past week i added a set of bapp hd springs and cam to try to pull a bit more out of it. the prob is there is alot more noise from the topend now and its running hotter than before. is it normal for the stiffer springs and higher lift cams to be louder that the stock setup? Everything looks to be ajusted right, carbs even running a bit rich right now. As far as it running hotter do i need to mess with the timming when running a bigger cam?

[torque]

when i did the top end in my bike with a hight lift cam i noticed more valve noise. i double and triple checked the valves and cam chain.

as far as jetting i had to go down on size on the pilot(but switched from a bassani to a supertrapp@the same time) and up on the main a few sizes. after lots of messing around i got it right

[shortline10]

High lift cam will give more rattle in the top end of the 200x you can use a straight weight oil like 40w-50w no 10-40w too thin IMO and as for running hot its all in the fine tuning .

The stock 200x carb on a modified motor IMO seem to run hot no matter what also higher the octane fuel the cooler the motor will run , try some VP 100 .

Timing might be a play also , your running an aftermarket cam so play with the advancer timing to make sure its not retarded to much .

[hippyplz]

I was hopping a lil extra noise was ok. did you notice yours running any hotter after putting in the cam?

[hippyplz]

Running a xr carb for now.i have 10w40 in it also so i will change that out tonight and play with the timing.

[torque]

i did not take any temp readings before or after. how do you know it is running hotter?

[shortline10]

The motor will get sluggish and you will feel the heat radiating from the motor .




i did not take any temp readings before or after. how do you know it is running hotter?

[torque]

no then i have not noticed any extra heat.

im running a simular setup 10.25 piston xr carb and a supertrapp with 93 octane.

[hippyplz]

I didnt even think about the fuel. I had some extra cam2 so i was running a 50/50 mix of that and 92 but now there is just strait 92 unlead in it. Thanks for the ideas i will play around with it some more tonight.

[hippyplz]

Ok i played with it a bit more and am more lost now than i was. I put some fresh 110 fuel in it and it seam to be running a lil cooler but then it died and will not restart for nothing. when i kick it over i can hear some air leaking and i checked the compression it was around 120. when i adv the cam one tooth it jumps to around 165 but still wont start. Checked the timing and the valves 4x now. Any ideas on what to do next?

[torque]

if you advanced the cam one tooth on the cam chain you will be out 10 + dreges on the valve timing. mot sur if that is what you are talking about but if it is you should line the timing marks back up.

[hippyplz]

Yeah thats what i did but why the jump in compression when its like that?

[oscarmayer]

ok when you set the crank to correct TDC mark and the cam itself w/o the chain to TDC it all aligns up withthe marks, but when you redo the cam to add the chain, it can fo 1/2 tooh forward or back. you are supposed to put it 1/2 tooth forward is correct. they never 100% align up. but it shoudl be slight forward. if you had set it to slight back, that is why comp changed. now that you have 165psi comp (still a bit low for 10.5:1 as you should be 195+, you can now see if your getting spark. are you getting spark? if you are, take the carb and intake off. take some good quality carb cleaner and spray down the intake port and kick it, if all else is working except fueling, then it will fire off and run for a sec and you can keep it runnign by spraying more cleaner in the intake port.

if no spark, you need to check for other problems. and also to ensure your rotor assembly is not 180 out. it can be disambled and end up 180out upon reassembly. so to check, when the cam is TDC mark and crank is , the line on the rotor should match up perfectly to the line on the black pickup. if it does not, your 180 out.

[hippyplz]

I didnt get to mess with till last night and the base gasket was seeping a bit so i pulled the motor to replace that and get a better look. Checked the valves no leaks. Going to put it back in tonight and try it again. Your right it is about half a tooth off so i will make sure its set advanced. I could prob get it over 165psi that was just a cup quick kicks and i could see the jump. it has good spark and the plug was wet with fuel but i will clean it out again.

[shortline10]

Thats why they made adjustable cam timing sprockets . If the crank has ever been apart or the bottom timing sprocket replaced it's prob off a little so the adjustable timing sprocket does the trick .

[hippyplz]

Hey thanks guys its up and running only thing a changed was the carb. When back to the stock one. the xr carb never seamed to mount real flush with the intake and even tho it wasnt leaking it still sort of bugged me. Other that that i dont know what i did different. Still going to play with the tunning a bit and look for a bigger carb but its running. Thanks for the help.

[shortline10]

I have a few NOS Big Al's adjustable timing sprockets if you need one ? This way you can get the timing dead nuts :lol: