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high revs and coolant


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dark8

 
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high revs and coolant

Sat Sep 03, 2005 9:32 am » Post: #1 » Download Post

Hi guys....did a search for coolant and found too many unrelated topics...
so here i am.

Just wanted to know if bike coolant is same as car coolant? i think i overpoured into the reservoir. Any way to drain some of it out? I had a look underneath the radiator but didnt seem to find any draining plugs etc.

Also, the engine is idling around 2k rpm after the engine has been running for a while. Is this normal? The bike is beginning to get hard to start when cold. It starts about 4th kick, and then seems like it will die so i give it some throttle, then it dies straight away. After restarting the bike and just letting it go, it will run ok, but blows lots of smoke. I know its a 2 stroker but the amount of smoke it blows is kinda getting ridiculous. Just wanting to know if this is normal. Thanks guys.
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Dave Ett
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Sat Sep 03, 2005 11:18 am » Post: #2 » Download Post

There is a coolant drain screw on the bottom of the lower cylinder - an M10 or M8, which doesn't seem to be doing anything else.

It's normal to smoke when cold, but with the engine up to temp the smoke should die down to practically nothing really.

Sounds like the compressin may be getting low - worn rings etc. Do a compression test to check the state of the engine. Should be about 120psi from both.
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Andy
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Sat Sep 03, 2005 12:36 pm » Post: #3 » Download Post

What colour is the smoke? Blue or white/grey?

Blue could indicate rings (but a little blue is normal), white/grey could indicate a crank seal on the clutch side.

I've come to the conclusion my crank seals are getting a bit suspect (30,000kms+) as it's becomming harder to start, and it only had a top end recently. Once started it runs OK, and at the top-end it flies along quite merrily, but low speed and starting are a pain in the ass! We've tried bloody everything to iron it out too, right down to making new X and Y pieces to try and clear the low speed fuelling up!!

Have you checked the transmission oil level. If it drops then that could show up a leak into the crankcase.
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Last edited by Andy on Sat Sep 03, 2005 5:53 pm; edited 1 time in total
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rc46

 
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is car coolant he same as bike coolant

Sat Sep 03, 2005 12:38 pm » Post: #4 » Download Post

Yup should be just fine!


Listen to Wise Dave, your bike shouldnt smoke when its warm! When was the top end last redone?
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Andy
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Sat Sep 03, 2005 12:50 pm » Post: #5 » Download Post

rc46... shouldn't your signature be "Now with added grrr!"?! Wink
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dark8

 
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Sat Sep 03, 2005 2:51 pm » Post: #6 » Download Post

no smoke when warm..

smoke only when cold...just grey white smoke...so i thought its normal...but maybe i keep imagining that its smoking more than when i first bought it.

its done 30000km when i got it (2 mths ago) was told by dealer it had just had rebuild done (dunno if i should trust him tho). My friend who used to own nsr told me the clutch feels jumpy and sounded different to the one he had...i got nothing to compare with as no one else i know has nsr...

anyone in melbourne australia wanna meet up and check my bike for me? Very Happy
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rc46

 
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With added Grrrr

Sat Sep 03, 2005 5:43 pm » Post: #7 » Download Post

Andy, it will be soon, have lots of GGGGGGRRRRRRRR, and it might even turn out Great! Laughing frustrating having it all sitting there, i wna put the pipes on but dont wana ruin my bike by putting the chambers on and not the jet kit...

DARK8 your clutch should be like any other, if its grabby it could be on the way out. Its not a dry clutch is it? DONT trust the dealer, do you have recipts to prove the rebuild was done? and what was done? NO then dont chance it! get someone to recomend a 2 stroke tunner to have a listen and if needed a look!
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Andy
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Sat Sep 03, 2005 6:00 pm » Post: #8 » Download Post

If there isn't any smoke when warm, then you may be OK.

Mine's always been a pain to start, right from day one (about 2000kms when I bought it) but with a lot of playing around it did get better. It's started to go back downhill again now though, so I will pull it apart over the winter for a full rebuild.

A dry clutch can seem to be a bit "grabby", especially when hot; a wet clutch can be the same if the bike has been stood for any length of time as the plates can "stick" together.

If you have an SE/SP with a dry clutch, then you will just have to get used to the feel. If it's a wet clutch, then drain the transmission oil, take the cover off, and clean the plates. Reassemble it all and put in some fresh oil, and Robert's your uncle's brother! Smile
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Steve C
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Sun Sep 04, 2005 12:40 am » Post: #9 » Download Post

Hey Andy
Let me know how you fix your low rpm problem. My mc-18 has always run very rich and smokes a lot at low rpm. I think I have a 135 pilot jet (the smallest I could find). It runs like a raped ape up top. I rode it to work yesterday-- 50miles on the freeway 70-80 mph most of the way-- soon as it goes to idle, it starts smoking really bad and feels way rich? Confused

I used to think it was a combination of problems. The fuel petcock leaking and the needles in the carbs leaking. When it would sit for long periods of time it would be hard to start and spit out a lot of spooge. I have changed the carbs, fuel petcock, and needles in the carbs. It seems like it was better for a little while. Maybe you are on to something...
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Andy
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Sun Sep 04, 2005 2:23 am » Post: #10 » Download Post

I've gone down to #35 pilots, but it didn't like it too much, so now I'm on MC18 #38's, which are shorter than the standard MC21 #38S's.

I increased the size of the pod filters (the ones now fitted are about 25mm longer - same diameter) as they were killing the top-end over-rev, and have also taken the hole in the X-piece out to 0.8mm which has helped. I'm running "C" needles on a very lean clip but it's still rich!

We also tried a set of stock TA22A carbs with the airbox and Ethos supplied 132/135 mains and it was still bad, so all that's left really are the crank seals. At least we knew then that we hadn't been doing anything stupid and missed the blindingly obvious!!

It does over-rev past 12500 now however, and will pull from further down than before, but it won't pull from way down like it should. Top-end is sweet though, and was proven last weekend on a 150 mile thrash across the county and back with 4 other Forum members!
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rgvsean

 
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Sun Sep 04, 2005 8:23 am » Post: #11 » Download Post

Sorry to jump on your thread but pod filters kill the low - midrange.

Have you removed the airbox? This makes carb tuning very tricky.

Just not sure from your post what you have now. If you got pod filters to work well that's news as I have never heard good things about them before.
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StephenRC45
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Sun Sep 04, 2005 8:53 am » Post: #12 » Download Post

Yeah hes using pods, i dont really like them but i also use them on my track MC21 and to be honest the thing is perfect. We did some runs on it and it will pull clean WOT from about 2,500rpm without even a hint of splutter. My MC18 was also the same on pods, that would pull clean right off idle. I do agree some sort of air box would be better though.

On andys we tryed removing the pods all togther and this helped over rev but didnt make any differance down the bottom.
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Luke F
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Sun Sep 04, 2005 9:43 am » Post: #13 » Download Post

Stephen

Of course your track 21 is perfect, think man of its pedigree and history!! Laughing
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StephenRC45
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Sun Sep 04, 2005 11:02 am » Post: #14 » Download Post

errr yes.. perfect in every way lol
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