NC30 rings/piston kits

**lostinflyz** · 14th July 2008, 20:23

Be careful boring out the VFR block. I've heard they are notoriously unreliable as most the stock bits (specifically crank and even the block) are pretty dubious.

High compression pistons would be good though. If anyone knows where to get some ive got a RVF motor lying round that might like them.

**motorbyclist** · 15th July 2008, 01:55

dont all bikes burn oil above 10000rpm at which point oil starts to force it's way past the rings on the downstroke?

Originally Posted by Chrislost

would you like to buy my left kidney for $12000

then i could afford a 450cc vfr with (aparently) 88HP at the wheel

those thinkgs are built to do 59HP and not much more. unless it's got a modded clutch and gearbox that bike sounds like trouble...

Originally Posted by lostinflyz

Be careful boring out the VFR block. I've heard they are notoriously unreliable as most the stock bits (specifically crank and even the block) are pretty dubious.

High compression pistons would be good though. If anyone knows where to get some ive got a RVF motor lying round that might like them.

yes, but provided the new piston/rod are no heavier than the standard the crank/case should be ok. too light of course and it'd need rebalancing though....

high compression pistons are always good

**more_fasterer** · 23rd July 2008, 14:51

Originally Posted by Coyote

I've been told they burn oil from new and you should be topping them up regularly.

I find that hard to believe. Mine has done near-on 90,000km and doesn't use ANY oil between services.

If the engine was never run in properly, then it would make sense that it burns a bit of oil.

Originally Posted by vagrant

450cc kit plus Ti rods

http://www.akhara.com/nc30/pistonrod1/index.html

I can't believe how short the skirts are on those pistons!

**Coyote** · 23rd July 2008, 19:13

Originally Posted by more_fasterer

I find that hard to believe. Mine has done near-on 90,000km and doesn't use ANY oil between services.

If the engine was never run in properly, then it would make sense that it burns a bit of oil.

Well it'd be a safe bet that mine was fucked from the beginning.

My bike won't be reaching 90,000kms for a few more years at this rate...

**Rback** · 23rd July 2008, 19:27

If it is smoking on a cold start then the valve seals need to be replaced. To test the rings -Once the engine is up to working temperature , hold the revs at around 4500-5500rpm (in neutral and stationary) for approx 30 seconds then give her a hand full. If white smoke comes out of the exhaust then the rings are showing wear. They can handle 70 to 80 hp easy. Give Greg Shaw at Planet Honda in Whangarei a call. He Knows the NC30 engine very well.

**monkey99** · 23rd July 2008, 19:37

Originally Posted by Rback

If it is smoking on a cold start then the valve seals need to be replaced. To test the rings -Once the engine is up to working temperature , hold the revs at around 4500-5500rpm (in neutral and stationary) for approx 30 seconds then give her a hand full. If white smoke comes out of the exhaust then the rings are showing wear. They can handle 70 to 80 hp easy. Give Greg Shaw at Planet Honda in Whangarei a call. He Knows the NC30 engine very well.

Does greg know much about RVF & parts?

also..parts your after for compression job are available at Econohonda now (22/07/08)

A top gasket set is $294.20, we have in stock
Lower gasket set is $120 if still available
Rings are $332
Seals work out at around $30

thats a verey tiny mortgage..or a bigggg Boot

**monkey99** · 23rd July 2008, 19:39

Originally Posted by more_fasterer

I find that hard to believe. Mine has done near-on 90,000km and doesn't use ANY oil between services.

If the engine was never run in properly, then it would make sense that it burns a bit of oil.

I can't believe how short the skirts are on those pistons!

Funny this is the guy who runs an AMA racae team in the US & has spent years developing racing V4's and have so much knowledge..more to the story but sad to say Mike is not racing anymore as he has a severe neck/back injury..but his team..

man they can do amazing things

**Squiggles** · 23rd July 2008, 20:37

Are the rfv and vfr pistons etc the same?

**racefactory** · 7th August 2008, 00:12

how many kms are you rebuilding it at?

**motorbyclist** · 7th August 2008, 01:05

57000 on the clock, plus atleast 5 that i know of that aren't on the clock

note i'm not rebuilding it till the summer, and the bike doesn't actually need it

**racefactory** · 7th August 2008, 02:05

what can really go wrong on these bomb proof engines?

valve wear.... what else really? Anyone broken the piston or ring?

Also- what temps is your motor running? These V4s really get hot! At least mine feels hot, it shows 70 on the reading which i guess is good?

**motorbyclist** · 7th August 2008, 02:24

mine varies from low to 90 degrees at which point i manually turn the fan on (the thermal switch died, so did the new one, cbf paying for another one, blame the 'homebrew' wiring loom)

i reckon mine reads about 70 under normal conditions, can go right the way up to 110 when you're thrashing it in tight twisties due to low speed and high revs, but fan usually sets that right.

before i did the manual switch bypass it got as hot as 120 one summer's day in slow traffic. thought i'd turn her off at that point, no harm done. though check your overflow hose is there, my one was missing and the reservior just dumped all over itself.

these things tend to "feel" hot as all the hot air has touble escaping the rear of the engine, the rear header pipes heat the cavity under seat/between legs, and when the hot air does finally escape it goes via the rider

the european models were fitted with oil coolers to drop a few degrees off the oil temp and thus further help parts life

common sense really; water/coolant mix boils at 110-120 degrees celcius, so keep it under 100 and it should be fine.

if there is an issue you should notice a lack of power before it seizes.... then you'll be glad it's relatively easy to do a complete engine rebuild on these things

**lostinflyz** · 7th August 2008, 09:17

yea they run stinking hot. my race one doesnt really even sit on the temp guauge when its hot. scarred the shit outta me for a while but the stack temp gauge is shit. should stay around 90 when u hoof it.