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CR500 PWK 39 help

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Reaching out to some 2T 500 gurus.

got. CR500 all new engine, reeds etc etc, the bloody thing is a pig to start. I have a new pwk39 carb. It came standard with a 60 pilot so I bought loads of lower ones in case. Anyway the bike is a sod to start and seems to throw fuel into the cases. If I take the exhaust off it's pooled up in the header pipe. I've been dropping the pilots down and down and it's now on a 38. It wouldn't start running till it hit 44. When it actually runs it sounds sweet as a nut. Ridden it up the road and it pulls hard. The fuelling issue is doing my nut. It has brand new v force 3 reed block. I did notice a slight gap round the petals when I had it off but thought nah cage is new. 

Everything about engine is new apart from gearbox, just had new head gasket as I've fitted decomp head.

im in U.K. So elevation is below 3000ft. Running 32:1 Castrol Power 1 racing 2 smoke oil.

standard main so think it's 160 ish, clip on middle, 1.25 turn on screw, 38 pilot (seems well lean) but plug always gets wet.

help please

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set your float level would be a great start, you might also want to tell us little things like what needle your running ?

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Float height seems spot on.

Just stripped carb for the umpteenth time. It's running the following.

175 main, CEJ needle on middle clip, 38 pilot, 1.25 turns on screw.

Took some pics if they upload. The black stuff in the pot is what I have just sucked out the crankcase. Bottom pic is what I see through my new reed cage.

 

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The spring loaded tip of the needle should be extended full when the tank of the float yoke just contacts it.   if the carbretor is used and the needle is worn or the spring is weak, you get that symptom.  richer than mine is slightly,  but not enough to make it flood.  fyi I have the stock reed block with dual stage reeds.   mine is 1.75 out with a 40 pilot.  

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It is, it's sat at 45 degree angle. Don't get no overflow issues or anything. Not sure on that reed cage of mine.

Carb is brand new never used.

I get pooling like this in exhaust.

 

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your reeds have seen better days, its impossible to tune a motor if the reeds are hanging open. flip the petals and check if you get a proper seal also check the cage for damage.

looking at the pooling in the pipe i have to ask is your coolant level dropping? i ask that because your pipe looks rusty inside.

when my reeds went like yours look my compression dropped a lot and starting became tough and when i did get it going it had a wandering and some times hanging idle.

your 500 will run and scair the daylights out of you and probably wheelie through the gears efortlesly even when it barley runs.

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If there is a gap in the reed petals that may explain your starting issue. Mine becomes a bear to start when reeds are worn.

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If the reeds end up being the starting issue you also might find that needle is a bit too rich. You're one clip richer than the standard needle now with the same diameter. I found the standard needle to be a bit too rich at 0-1/4 throttle and the taper a bit too lean. Standard needle is CGJ, ended up finding DGL runs better.

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dump the V Force 3 and the silly plastic, go OEM or Rad Valve. 

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The pipe was a bit rusty in the header when I bought it new.

The fuel just seems to emphasise it.

I'm hearing a lot on these reeds. Annoying me big time as they are brand new. This engine has 2 miles on it. 

When I say it's a new engine I don't mean rebuilt I mean NEW, out the box factory new. All the engine cases, cylinder, head, piston, crank, reeds, carb etc are all brand new out the box. It's a CR500AF that I built from scratch myself. I'm an ex motorcycle engineer so I know my way round a bike, this one like the back of my hand. Just this fueling issue is causing me to loose hair. I can't believe that a new reed so called performance reed cage can be bad, but I'm sure it's not the first time.

What are people's opinions, boyesen rad valve or OEM?

The offending beast below.

 

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i hate to be the one to tell you but when it comes to reeds on your cr500 stock new honda oem is hard to beat, what year frame did you convert? i converted an 03crf450 to run my 1985 cr500 i always kinda liked all that useless explosive stupid power compared to the newer cr500 motors.

cheers on building your own machine, when you built it did you do a leek down test ? 

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Converted a 09 CRF250R frame. No leak down test as didn't think I needed to on new engine. Got compression to spare. Problem is in the UK cr500 parts are hard to find and cost a packet. I had to import all my new cases etc from USA as it was half the price. I can get a new complete oem reed cage with new connector boot (have to butcher oem one to fit vforce reeds) from USA for $161 posted to my door. The reed cage is no longer available here in UK but costs £162 alone plus another £64 for the boot.

Think I'm gonna try oem reeds. The guy I hot the carb from is a specialist and has been trying to help me get this right. Even he said the reeds look bad and the pilot of 38 is way too low for a 500. He thinks it should be more like 46+ as a starting point. He supplies them with a 55.

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Took another pic this morning after flipping reeds over. Only seems to be the middle pair that have the gap. Outer pair seem OK.

These are brand new out the box by the way. We're fitted and run for 2 miles and had nothing but starting issues since fitting with new carb.

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They work well for many bikes, but well known to be rubbish on the 500. 

Edited by DEMI
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get the new reeds and get a bigger pilot jet in that bike, likley it will run with the 38 when you replace the reeds but picture getting up in rpm than let off the throttle ding ding ding coasting  and the only thing lubricating your new motor will be that little 38 pilot jet.

i really think you would be doing your self a favor to do a leek down test on your motor , their is an excelent sticky on build it your self leek down tester on the top of this page,  its so easy to do on a 500 because their is no power valve stuff to contend with. confirming no leeks before wasting time trying to tune is priceless .

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Those 2 stroke leak down test kits are hard to find here in UK. Getting hold of those rubber expansion bungs seem non existant, all US stuff. Making the actual tester don't look hard, just can't find those bungs.

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lol i dont think your looking verry hard, its comon stuff in marine and auto parts stores here. if you want i will get and send you one ? just cover postage and purchase- i take paypal i,m in canada v4n2b7

any more problems? lol serious i would help you out easy

 

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Thanks buddy, typed in various things to Google all came back US sites. Went on eBay found hundreds all different sizes but again all US not a single UK seller.

Like you say common in auto and marine stores just not here for some reason.

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