Cr 500 af

[Russell]

well, I got the parts yesterday, but life kept me from doing the work...
New reeds/cage


some modification is required



installed after a bitter battle with float levels


and bike is done (okay, I have one aluminum bit to weld on; but that's coming later)

What is that new part? I don't know any thing about Bikes.

I think it would be cool if you got video of you on the Bike and / or helmet cam.

[SuperBuickGuy]

a 2 stroke motor pulls air/fuel from the carb using the vacuum created by the piston moving up in the bore. To keep the air/fuel from reverting back out through the carb during the down-stroke, the reeds close allowing the air/fuel mixture to pressurize in the case. Once the piston uncovers the intake port, the air/fuel mixture rushes into cylinder, is compressed, then is ignited. no valves, nothing moving but the reeds and the piston.... it's what makes them have such a great power/weight ratio

I'm sure I'll use my gopro on a riding day.... problem is there's a lot of vibration, so the picture could be pretty fuzzy

[Beagle]

I think he's talking about what did you modify in the reed cage... and I'm being a little nitpicky about it, but it's more accurate to say they have a potentially higher power/weight because it only takes 2 strokes for a cycle to complete versus 4. Every revolution has a power stroke. The commonly used rotary valve 2 stroke cycle petrol engines enjoy the same advantage, as do the other types of induction that don't use reed valves, like piston port timing in fairly common small engines (example...RC, weedeater, blowers). There are two stroke cycle diesel engines that use a cam and poppet valves and the blower is actually not to compress the intake but scavenge the exhaust.

carry on. It's one of those things I get hung up on... "The two stroke cycle" is correct. I don't want a 2 cycle because if it only lasted 2 cycles, it'd be boring.

Russell, the black wings got cut off is what I see. You can see what looks like witness marks where the saw got up against the aluminum from the "guide" picture above. The original reed cage / intake manifold design was modified for the new reed cage.

From this:


to this:



black part (probably phenol?) was cut off so this would fit:




Either that or I'm on the wrong planet again and missed the question. haha. Good show.

[Russell]

Well both post helped. I have never heard of a reed cage. Still learning about 2 Strokes. My guess is that power has to do with twice as many power strokes per rpm

[BBR]

I have read that a pwk off a KX500 is a good swap for troublesome pj's.

[SuperBuickGuy]

Well both post helped. I have never heard of a reed cage or what they do. Still learning about 2 Strokes. My guess is that power has to do with twice as many power strokes per rpm

and lighter - no valves, cam(s), etc.

I'll have to look at the pwks, thanks bbr

[Beagle]

Russell is a Four Stroke Poster (that's four posts for one!)

Detroit two stroke diesels have cams and valves SBG... maybe only for the exhaust, but it's there.

[SuperBuickGuy]

weeeeeeeeeeeeeeee
waaahhhhoooooooooo

hang onnnnnnnnnnnnn

weeeeeeeeeeeeeeeee

so concludes today's CR500af ride at the OHV park

[STINEY]

Ahhhh.....the sweet sounds of success!

What is the scoop on the OHV park? Acreage, terrain, access, facilities?

[milner351]

two stroke dirt bikes.... no throttle required - just and on/off switch!

ENJOY!

[SuperBuickGuy]

Ahhhh.....the sweet sounds of success!

What is the scoop on the OHV park? Acreage, terrain, access, facilities?

270,000 acres of 20 year old trees.... lots of trails, streams, camping, pit toilets and nice people.

[SuperBuickGuy]

this is astounding, I ordered from Bike Bandit yesterday (they're in Idaho), and received my order this morning.... wow.

[hauen]

I love Bike Bandit. When I owned any older bike that wasn't a Honda, they loved me.

[SuperBuickGuy]

well, I rang this thing out on Sunday at Washington State DNR land, and realize I really need to get a few things solved.



First the expansion pipe has been welded so many times that I think it's more weld than pipe anymore - so a new one is on its way.
It is LOUD, and that could get me in trouble, so I ordered a FMF Q muffler and spark arrester

and finally, I really need to tune this thing. I used to rely on my brother and Dan Bros in Clackamas to tune my bike; but they're not here... it runs well at idle, and it works awesome when I'm on the pipe.... but between those two points it plays hit n miss. I've been reading up on tuning the carb, and it doesn't sound like my jetting is off, just the air bleed - caveat is, though, the exhaust has to be good - and right now, it's not because the expansion pipe is cracked.

oh, and that fuel tank on the rear... bad idea. Ah well, I rode pretty hard for 2 hours and burned about 3/4 gallon of fuel. The tank has just over 2 gallons capacity (it had 2.9 until I reformed the bottom to clear the 500)... so there's little need to haul the tank with me. Though, I think I'm going to try to find a reserve valve for the tank (the valve is in line with the fuel line; so it doesn't have a reserve)

[SuperBuickGuy]

Time to start dialing this in.... after the motor, I'm going to do some suspension work - after riding for 4 hours, the suspension seemed to lose all compliance - more specifically, the rear shock. As I used the shock from the cr500; it wouldn't surprise me to find out I need to swap that for the crf shock... especially since I think I overheated the fluid (the reservoir was pretty warm).

anyway, today's job
the pipe is cracked


the pipe has been welded a few times.


the replacement, a FMF Gnarly pipe... this pipe is for more bottom end and is well suited for the riding I do - also note the Q muffler/arrester. It's quieter than my other one, and should keep me from getting a noise ticket... something I should be concerned about with the old muffler



pulling it apart


so here's where I'm at tonight - dry fit. I need to get high temp silicone and I have to cut on these brand-new pipes.... ugh, the joys of modified bikes


I'm ordering a carb for it as well, a bit larger and brand new