2003 CR250 ignition

2strokeforever · Post by **2strokeforever** » November 11th, 2011, 8:43 pm

i had a small crack in the pipe, with the 500 stuff it ran pretty normal, with the 250 stuff it surged without changing anything else, got it fixed and the 250 stuff dosent surge much anymore
im guessing the engine builds more vacuum with the 250 ignition? making it more sensitive to air leaks

also i think advancing the timing (on the 250 stuff) made some surge go away

craigf40 · Post by **craigf40** » November 11th, 2011, 8:55 pm

hey gmbond
yes you need to slot the current slots about 10mm more so you can move it clock wise...you have to move that plate alot check your marks on the fly wheel to key way the very different

Gmbond · Post by **Gmbond** » November 12th, 2011, 8:25 am

Well I advanced within the existing slot and it seemed slightly better, so I slotted the plate about 5mm and tried it advanced, seemed to start and run better again.

So then slotted further about 10mm

Seems to start easiest and idle and rev up the best. I wasnt able to ride the bike for any testing, I'm in a suburb....

So until i can test ride it's kinda grey area still.

This is what I've landed on for where the stator plate bolts will be when installed.

Only issue I currently see the bolts are now outside (on the edge) of the machine spot which levels the stator plate when bolted to the motor. I am thinking a shim washer will be trimmed and epoxied into place.

As well the clutch lifter arm is now sitting nearly above the arm from the stator plate tha keeps it from walking out. Another fairly easy fix I think.

Gmbond · Post by **Gmbond** » November 12th, 2011, 9:39 am

Ah what the hell may as well toss up a pic of what this all belongs to.

(flywheel is loose on the crank, no stator installed here)

Gmbond · Post by **Gmbond** » November 14th, 2011, 11:16 am

Can anyone assist in how i should be timing this? (using a digital inductive pickup snap on timing light)

My gut/experience is to set the motor to TDC and make a mark on the stator to align to to the T mark on the flywheel. Start the motor and hold at 4000rpm (per the 03 cr250 manual)

align the F mark on the flywheel with my TDC mark on the stator (moving within the slots to align.

does this sound right?

thanks!

http://www.youtube.com/user/500bigbore · November 14th, 2011, 12:15 pm

i'd rev it to 1000rpm, The timing should be 10 degrees here. I'd set the snap on light at 10 so it should show you how far off you are, letting you get the stator dialed in to 0 where you can mark it.
to check it at a higher rpm its spec is 16 degrees at 2500 and 12 at 5000

hope this helps

craigf40 · Post by **craigf40** » December 16th, 2011, 12:25 am

Gmbond wrote:Can anyone assist in how i should be timing this? (using a digital inductive pickup snap on timing light)

My gut/experience is to set the motor to TDC and make a mark on the stator to align to to the T mark on the flywheel. Start the motor and hold at 4000rpm (per the 03 cr250 manual)

align the F mark on the flywheel with my TDC mark on the stator (moving within the slots to align.

does this sound right?Hi gmbond yes thats exactly wat i did get your motor on tdc and remark your fly wheel you will then see how much the 250 mark is different... you can then use your timing light... i am home now so il take some pics and mail them to you

thanks!

Gmbond · Post by **Gmbond** » December 16th, 2011, 3:25 pm

Craigf40 - I would love to see some installed pictures, as your setup sounds like it runs mint!

You are running the mikuni tps carb also, in Canada, the 03 did not have tps, the 04 was first year of it.

I haven't been able to do much else to my bike, will be sticking a new left side crank seal in basically just for the hell of it while it's all apart anyways.

maddog1927 · Post by **maddog1927** » January 7th, 2012, 1:23 pm

Any ride report? Sid you stick with a 10deg advance?

Gmbond · Post by **Gmbond** » January 7th, 2012, 3:50 pm

Sorry no ride report, havent ridden or even started the bike since I posted the pictures, usually this time of year we've got 2 feet of snow and freezing cold... Despite the unseasonably warm weather I kinda pushed the bike toys to the back burner and have been working on other projects.

I am also still hoping/counting on CraigF40 posting an installed photo showing his alignment on his bike that he has up and running.

maddog1927 · Post by **maddog1927** » January 22nd, 2012, 7:50 pm

I fit an '02 250 with an '04 125 cdi.

No ride report yet, but I did get it started.

the '02 + flywheel is sooooooooooo sexy.

maddog1927 · Post by **maddog1927** » January 22nd, 2012, 8:02 pm

Please note that the regulator / rectifier is required. Part # 5 here

http://www.servicehondapsn.com/fiche_se ... &fveh=3273

This messed me up. I did not know it was required, so I did not buy it with one of the 250 sets I got... but never fear, always a back up around my garage. The other inconvenience, I had just bragged to my friend that was over while I was setting up the ignition, that my '02 125 frame did not have the mount on the LH spar for the regulator / rectifier, so I did not have to cut it off, which is a popular thing to do on the 250 or '04+ 125 frames.

Well as it turns out, those mounts would have come in handy. I had to build a custom mount.

Bragging sucks, every time I do it, I get cut down right after.

Do not cut these off if you build a gen 3

I used an' '02 125 frame which did not have those mounts so I mounted here

maddog1927 · Post by **maddog1927** » January 23rd, 2012, 8:27 am

I used autocad to make degree templates to tape to the flywheels. I made a pointer that bolts to a stator cover hole, got to TDC using a dial indicator through the spark plug hole. I used a harbor junk timing light, a tachometer, and a note pad to record different timing curves.

Please note these #'s are not gospel, but reference.
the 97 500 was set at sock marks. My guess is the '93 and '97 500 are actually the same, and I know that rss's #'s are more accurate. the 250 stator was rotated 6.5 mm advanced from the stock hole. I need to either find 2strokeforever's mm to degree conversion or bust out auto cad to figure out, but I am going to guess that is about 8 deg advanced from the stock 250 hole.

93 500 '97 500 '02 250 '02 250 w/ 04 125 cdi
(rss post)
2500 24 21 14 22
3000 24 21 10 21
4000 24 20 10 20
5000 22 19 10 18
6000 19 15 6 17
7000 15 10 5 14
8000 12 10 3 8
9000 8 8 0 5
10000 0 0 0

I will be running the 250 w/ 125 CDI set up, probably advance 2-4 deg from here, the make any changes I feel needed by the "seat of the pants feel" approach.

Rotary table and fixture used to elongate holes:

Tach:

Pointer / degree template on '02 stuff:

Reference photos of Clocking of stator :

asteroid500 · Post by **asteroid500** » January 23rd, 2012, 2:01 pm

Its so refreshing to see the simple things 1st ... ie.. TDC & marking the flywheel.
My thread got Tech heavy, not what it origionaly started out to be, but we have some very Tech savy members here at Banned & it all made it so much better to read. Oh & it works.
Awesome tread ... love ya work ...

Gmbond · Post by **Gmbond** » January 23rd, 2012, 8:05 pm

Thanks Maddog!

Those are some great pictures and really show the alignment!

How come you went 125 cdi?

Starts easy? and runs good?

maddog1927 · Post by **maddog1927** » January 24th, 2012, 7:00 pm

I like the more aggressive timing curve of the 125 cdi.

Starts and runs good. No ride report as of yet.

Takes a few seconds to switch the CDI. Next time I go to the dunes I'll try both.

maddog1927 · Post by **maddog1927** » January 25th, 2012, 7:28 pm

What would be the harm if I advanced a few more degrees, with regards to the clutch actuator arm retainer tab would no longer be effective?

craigf40 · Post by **craigf40** » January 25th, 2012, 10:28 pm

maddog1927 wrote:What would be the harm if I advanced a few more degrees, with regards to the clutch actuator arm retainer tab would no longer be effective?

i been meaning to take some pics of mine for gmbond just neva get the chance il see if i can today mine is advanced alot and i also was a bit worried about the clutch pin but iv had no issues with it

maddog1927 · Post by **maddog1927** » January 29th, 2012, 9:03 am

I advanced, for reference bottom of the 3/16"ish round of the clutch actuator even with the top of the retainer tab, and rode for about 2 hrs at the dunes. It worked well.

Gmbond · Post by **Gmbond** » February 4th, 2012, 8:20 pm

Thanks Maddog for the ride report, I am itching for spring to try mine out,

Great reference on the location of the tab to clutch arm, that'll give me a great place to get going from

Post by **AlisoBob** » February 4th, 2012, 9:46 pm

maddog1927 wrote:Pointer / degree template on '02 stuff:

NICE!!!!!

Gmbond · Post by **Gmbond** » May 12th, 2012, 7:00 pm

Okay so I FINALLY got back out on my bike.

First ride with

-2003 CR250 ignition
- 38mm PWK airstriker carb
-Tubliss front and rear
-New OEM reeds

So basically I had a lot going on and had messed with many things.

The biggest change I would say I noticed was the low rpm capability of the ignition system... It will idle down lower than you should ever be able to run a big bore two stroke, and it's smoother throughout.

I can't comment on wide open throttle top power or anything like that, my ride was all sandy tight single track.

For timing I set it up with the top of the clutch retainer tab on the stator flush with the bottom of the "nub" of the clutch actuator arm.

BannedCR500Riders.com

2003 CR250 ignition