Trying to fix cam timing to run a 94 cdi on a 2005 ninja 250

[Nicosiacustom]

I need help i have an 05 ninja. 250 and had to change the head because the previous owner striped the spark plug they also tryed to advance the cam so i got the head on and it started but has no power so what im trying to do is change the timing so i can run a 88 to 94 ignitor i know i need to line up the marks what i dont know is what direction the cams are supost to face on the cam lobes on the 88 -94 and other wise the duration there open is the valve in the same spot as the 05 when fully open can anyone have a picture of the cams for an 88-94 at top dead center with the marks lined up so i can see the degree of the cam lobes???

[DannoXYZ]

Ignition timing and cam timing are not same thing. You can change one (or both) and it won't affect other. They are independent properties.

Cam timing = phasing of cam relative to crank position. Adjustment isn't really possible in finer increments of one tooth on cam-gear. Being off by one-tooth may result valves hitting pistons.

Ignition timing = phasing of spark relative to crank position. Spark is triggered by pickup-coil sensor that measures crank-position. ECU/ignitor receives these pulses and calculates crank-position and speed to fire spark at pre-programmed intervals based upon RPM. Adjustment isn't really possible without re-programming ECU. Easier to get ECU with different programming.


Get manual and follow valve-clearance procedure and make sure cams are aligned properly.

[Nicosiacustom]

I know that i have an 06 and an 05 whoever had it before changed the sprocket on the cam it runs with the 05 ecu but has no power with a load on it and have plenty of conpression. I made an adapter that plug into the harness and the ecu from a 94 ignitor i was thinking he over advanced it because the lobes are not in the same position as the 06 bit there the same cams was trying to find a picture of the cams on a 88-94 to see where the lobs face when the marks are lined up.

[DannoXYZ]

Again, cam-timing is completely independent of ignition-timing. You do not adjust cams in order to run any particular ignition map.

There is only ONE posiiton for cams because sprockets have fixed holes and there is only ONE way to install them. If cams are not set exactly in stock position, you will run valves into pistons and destroy engine. Get manual and follow cam-installation and timing procedure. Same sprocket is used on both intake & exhaust cams, be sure to align proper mark on each cam as dictated in manual.

Here's cam-specs for '88-'94 bikes:
intake open 30 deg BTDC, close 70 deg ABDC, duration 280 deg, lobe-center = 110
exhaust open 70 deg BBDC, close 30 deg ATDC, duration 280 deg, lobe-center = 110

And cam-specs for '95-'07 bikes:
intake open 26 deg BTDC, close 66 deg ABDC, duration 272 deg, lobe-center = 110
exhaust open 66 deg BBDC, close 26 deg ATDC, duration 272 deg, lobe-center = 110

Note that cam-timing for '88-93 and both '05 and '06 are exactly the same!!!

Now, if you were to get slotted cam-gears, like these, you can adjust your cam-timing. I use them on my race-bike and even though they have +/- 5-degrees adjustment, bike stops running beyond +/- 4-degrees adjustment in either direction. Most power was achieved with 2-degrees retarded exhaust and 3-degrees retarded intake. This setting reduced high-RPM torque-drop and raised peak-power into higher-RPM range of 12.5k vs. stock 11.5k

There's absolutely no way you can eyeball 2-3 degree rotation of cam-lobes compared to stock. Both '05 and '06 use same intake & exhaust cams part# 49118-1054 with exact same gear #12046-1085. Show us picture of '05 vs. '06 cam-gears you have. I think there's something else going on here.

Also read up on cam-tuning here:
https://www.ninjette.org/forums/showthread.php?t=167264
https://elgincams.com/camshafts/
https://www.musclecardiy.com/perform...mance-engines/

Note: these bikes have 26-27bhp @ wheels and aren't gonna rip your arms off. Or your carbs are clogged and needs thorough restoration. Most likely engine is fine.

[Nicosiacustom]

Ill get pictures of both tonight and the carbs clean with new jets

[Nicosiacustom]

So the ecu from a 88-94 should run the bike if you changed the pins and give you a higher rev limiter

[DannoXYZ]

Originally Posted by Nicosiacustom

So the ecu from a 88-94 should run the bike if you changed the pins and give you a higher rev limiter

Yes. There’s slightly more ignition advance (on non-CA boxes). You’d need dyno-test or stopwatch at track to see difference. Not really that significant.

[DannoXYZ]

Well, only ONE correct position for cams. But 2 different ways to bolt cam-sprockets on (2 sets of holes). For exhaust cam, line up cam bolt with “E” on gear. Intake cam should line up with “I” mark on gear before bolting together. You need to get manual.

Here's thread with photo of cam-gear orientation. Bolt cams to proper set of holes so they're oriented as shown.
https://www.ninjette.org/forums/show...01&postcount=4

1. note cams and gears are identical between '05 & 06' models. Same cam is used for both intake & exhaust side. Only difference is which set of holes in gears they're bolted to.

2. when properly oriented (with engine at 2T mark), cam-lobes on #1 cylinder are splayed apart by exactly.... 110-degrees!

[Nicosiacustom]

So i fixed the cams he changed the needle jet holder emission tube with one that has 16 holes in it so its fluiding out the whole time no power i think it came out of the dyno jet kit but never changed the stock exhaust

[DannoXYZ]

So many questionable mods by previous owners! Best to restore everything back to bone stock! Bike will never run as well as 100% stock bike!

[Nicosiacustom]

What about the California cdi will that work

[DannoXYZ]

No, CA ignitor has less ignition-advance. Same as ‘95+ bikes.