Dan's NC30
- iDemonix
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- Bike owned: '92 NC30
- Location: Banbury, Oxfordshire
Dan's NC30
I made this topic over at 125ccsportsbikes as I've been a member there for years, thought I'd make the same thread here - so if you're a member on both forums prepare to see double.
I know a lot of you (and I do definitely) love a good project/diary thread so I thought I'd start one of my own about my NC30. I'm not rebuilding, stripping or anything drastic. This thread will serve more as a log of what I've done and a personal reminder of what I still need to do, so don't expect thrilling updates - but I've got an SLR and an NC30 - so expected pictures.
My bike is a '92 NC30 in black and red. The reason I bought this particular NC30 is the colour scheme which isn't that common, but I love. The bike came to me with a leaking rear manifold, several leaks on the exhaust link pipes, non working indicator circuit, high beam relay bodge (most wires in the loom to the lights had melted), various tacky gold bits and so on. The tack was removed and replaced with originals;
Work To Do
I know a lot of you (and I do definitely) love a good project/diary thread so I thought I'd start one of my own about my NC30. I'm not rebuilding, stripping or anything drastic. This thread will serve more as a log of what I've done and a personal reminder of what I still need to do, so don't expect thrilling updates - but I've got an SLR and an NC30 - so expected pictures.
My bike is a '92 NC30 in black and red. The reason I bought this particular NC30 is the colour scheme which isn't that common, but I love. The bike came to me with a leaking rear manifold, several leaks on the exhaust link pipes, non working indicator circuit, high beam relay bodge (most wires in the loom to the lights had melted), various tacky gold bits and so on. The tack was removed and replaced with originals;
Work To Do
- Fix clutch (serious slippage, new clutch plates + possibly engine plates + springs)
- Balance carburettors
- Find where oil is leaking from
- Replace tacky indicators
- Get wheels powdercoated - paint is flaking off
- Solve mysterious rattle at low speed throttle
- Fix indicators - replaced relay and some new wire
- Fix rear exhaust manifold (had someone else do this as I was new to the bike + no tools)
- Remove exhaust + have all holes + cracks welded
- Rewire light circuit + fit high beam and relay mod.
- Replace L/H switchgear
A roaring V4 is the summer soundtrack.
- iDemonix
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- Posts: 651
- Joined: Tue Aug 24, 2010 10:26 pm
- Bike owned: '92 NC30
- Location: Banbury, Oxfordshire
Re: Dan's NC30
I did the exhaust a month or two ago, took a few phone photos.
For those interested; I did this without removing the rear shock - it can be done, it's just a f**king pain.
It was a nightmare of a job, was a fair pain getting the exhaust off - but this was nothing compared to getting it back on! Especially since the welding of all the Y joints had caused a slighty change in shape of the pipes. The biggest pain was getting the rear pipes to bolt up the rear manifold properly, whilst lining up the front.
I started by stripping the lower + upper fairings. I then removed the heat shield that covers the rear exhaust pipes and used a spare piece of wire I had to tie the rear brake + heat shield assembly out of the way near the coolant. Top tip: if your allen key bolts that hold the rear brake mountings on are solid, insert the allen key then use a G clamp on the allen key for leverage. Works a treat.

Then using a 10" extension bar and knuckle joint (extremely helpful for undertaking this task) I removed the 7 bolts (2x each front, 3 in the rear manifold). I can't remember which order I took the pipes off, I believe I pulled the front pipes out of the cylinder head and rotated them, allowing me to pull them off the system as they joined underneath the sump. Removing the rear pipes from the manifold was difficult, I poked a flat bladed screwdriver in above the right hand of the frame and prized them apart. I then poked a screwdriver through from the left hand side, rested it against the aluminium piece that holds the pipes on and gave it a few whacks with a hammer.

It had several cracks in between each Y joint - (and an update; it's recently cracked again somewhere, ffs!) which I had tig welded by a guy in Stapleford (GIA Engineering - top bloke).

I also used this opportunity to give the pipes a MUCH needed clean with some sandpaper, wire wool and autosol metal polish.
Getting the pipes back on took many hours in to the night, eventually I got help off my dad. I scraped out the old sh*tty gaskets that were long f*cked, I didn't have any time to wait for Honda gaskets to arrive as I needed the bike asap - so I went to the local Yamaha garage just before closing and picked up a set of gaskets the same size that fit perfect - from a Yamaha 125 IIRC.
People have techniques about lining up the rear or the front first, personally I tried all the methods and each was a b*tch. In the end I think my dad held the front pipes in place whilst I hammered the rear ones on to the bolts. As you can see, for reasons unknown, the front screws didn't line up at all;

Unfortunately after hours of getting to this stage, I had to remove the pipes again. I took the front pipes off and slid them back on to exactly where they were before and pushed them in place. Even though I absolutely coated the gaskets in grease they didn't like sticking on the front cylinders, many a curse word and screwdriver were thrown about.
Eventually I got the front pipes in and tightened them all bit by bit until they felt solid. Then I did the same for the rear pipes using a knuckle joint and extension bar.

I think the gaskets I used were a touch big, because for some reason I can't get the plate around the rear pipes to meet up with the rear manifold perfectly, there's a few mm gap. There's a ticking noise somewhere on the rear of my engine, I suspect it might be this joint - but I'll be damned if I'm taking it back off ever again if I can avoid it. Besides, the bolts were rock solid tight and with the gaskets in place too - no air should be escaping.
Ball ache of a job, but finally my bike ran properly again. Also I'm aware my engine+rad was filthy at the time.
For those interested; I did this without removing the rear shock - it can be done, it's just a f**king pain.
It was a nightmare of a job, was a fair pain getting the exhaust off - but this was nothing compared to getting it back on! Especially since the welding of all the Y joints had caused a slighty change in shape of the pipes. The biggest pain was getting the rear pipes to bolt up the rear manifold properly, whilst lining up the front.
I started by stripping the lower + upper fairings. I then removed the heat shield that covers the rear exhaust pipes and used a spare piece of wire I had to tie the rear brake + heat shield assembly out of the way near the coolant. Top tip: if your allen key bolts that hold the rear brake mountings on are solid, insert the allen key then use a G clamp on the allen key for leverage. Works a treat.

Then using a 10" extension bar and knuckle joint (extremely helpful for undertaking this task) I removed the 7 bolts (2x each front, 3 in the rear manifold). I can't remember which order I took the pipes off, I believe I pulled the front pipes out of the cylinder head and rotated them, allowing me to pull them off the system as they joined underneath the sump. Removing the rear pipes from the manifold was difficult, I poked a flat bladed screwdriver in above the right hand of the frame and prized them apart. I then poked a screwdriver through from the left hand side, rested it against the aluminium piece that holds the pipes on and gave it a few whacks with a hammer.

It had several cracks in between each Y joint - (and an update; it's recently cracked again somewhere, ffs!) which I had tig welded by a guy in Stapleford (GIA Engineering - top bloke).

I also used this opportunity to give the pipes a MUCH needed clean with some sandpaper, wire wool and autosol metal polish.
Getting the pipes back on took many hours in to the night, eventually I got help off my dad. I scraped out the old sh*tty gaskets that were long f*cked, I didn't have any time to wait for Honda gaskets to arrive as I needed the bike asap - so I went to the local Yamaha garage just before closing and picked up a set of gaskets the same size that fit perfect - from a Yamaha 125 IIRC.
People have techniques about lining up the rear or the front first, personally I tried all the methods and each was a b*tch. In the end I think my dad held the front pipes in place whilst I hammered the rear ones on to the bolts. As you can see, for reasons unknown, the front screws didn't line up at all;

Unfortunately after hours of getting to this stage, I had to remove the pipes again. I took the front pipes off and slid them back on to exactly where they were before and pushed them in place. Even though I absolutely coated the gaskets in grease they didn't like sticking on the front cylinders, many a curse word and screwdriver were thrown about.
Eventually I got the front pipes in and tightened them all bit by bit until they felt solid. Then I did the same for the rear pipes using a knuckle joint and extension bar.

I think the gaskets I used were a touch big, because for some reason I can't get the plate around the rear pipes to meet up with the rear manifold perfectly, there's a few mm gap. There's a ticking noise somewhere on the rear of my engine, I suspect it might be this joint - but I'll be damned if I'm taking it back off ever again if I can avoid it. Besides, the bolts were rock solid tight and with the gaskets in place too - no air should be escaping.
Ball ache of a job, but finally my bike ran properly again. Also I'm aware my engine+rad was filthy at the time.
A roaring V4 is the summer soundtrack.
- iDemonix
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- Posts: 651
- Joined: Tue Aug 24, 2010 10:26 pm
- Bike owned: '92 NC30
- Location: Banbury, Oxfordshire
Re: Dan's NC30
Now, on to the electrics. This wasn't physically taxing at all, but oh my god was it confusing. My bike came with an external switch for high beams and no relays for high OR low beams, it also came with melted wire everywhere.



I started with no experience with how electric works, so I downloaded a For Dummies book and read it cover to cover in a night. You can learn anything.
I decided the best way to figure out the maze of electrics behind my headlights was to draw a crude schematic of what was happening. I probably used the wrong symbols and so on but I understood it and that's all that mattered.

After stripping away the old switch and cutting a few wires, I wound up with two wires that when I put power through them lit up either the main beam or full beam. The wire with the yellow tape wrapped around it was the wire for the high beam. I found this out by using a light-up screwdriver and poking all the sockets behind the clocks, I eventually found one with power and using spare wire I had lying around I made a connection to each of the two wires - which lit up the bulbs.


Great. My plan was to make the electrics work as standard but without the low beam relay. Once I'd achieved that I'd put relays in to prevent any future problems.
The following colours of wires are from memory, so if you're undertaking this, ask questions and use the wiring diagram in the Haynes.
I got my new switchgear from a member on 400GB and using a continuity tester, I made a table of which cables did what. I eventually discovered that a black/red cable was delivering power to the switchgear and when the high beams were engaged, power (I think) came back down a white wire. I think I may of got colours/directions wrong as this was a month ago. This was how the switch worked that was bodged on;

I found another wire (blue maybe?) that had continuity to the power on sidelights being toggled. I ran a wire from these terminals in the left hand blocks to the two wires that led to my lights. Would you believe it, it worked! Now I had a basic working circuit without relays, I followed the Haynes book of lies schematic and wired in a relay (a quick nip to halfords to fetch two) using tape. Once confirmed it was working, I crimped on four spades and pushed them on the relay - then lathered it in tape and tucked it away. The relay is a bit big but you can't see it behind the fairings so who cares.
Now on the right side of the bike I found a big lump of tape, after unravelling it, I discovered four spades with connectivity to the left hand switch gear - looks like someone had an attempt at a high beam relay before but gave up maybe? Anyway, again with a continuity tester I discovered which wire had power back on the high beams being engaged and wired a relay using an online guide from 400GB. Rather than blow bulbs, I used my light-up screwdriver jammed in to a terminal on the back of the clocks, when I engaged high beams it lit up - I'd never had a working passing button either but even that worked!
I taped up the high beam relay and poked it in the frame as much as I could, it's hidden enough for me. As part of the bodge, a wire that should deliver power to the high beams DID come in to the block behind the clocks - but then when plugged in to the other terminal block it didn't go anywhere. So I cut the wire before it went in to the block behind the clocks and intercepted it with another cable. I ran this cable to that black wire with yellow tape from earlier. Works!
I taped everything up and tucked it all away as much as possible. It took me a few nights of tinkering and testing and writing down what colours and what terminals were doing what and when, but it was trial and error and I learned a LOT about electrics!

It all works now and has done for months, it could still do with a better tidy up behind the lights, but for now it'll do :)
Dan



I started with no experience with how electric works, so I downloaded a For Dummies book and read it cover to cover in a night. You can learn anything.
I decided the best way to figure out the maze of electrics behind my headlights was to draw a crude schematic of what was happening. I probably used the wrong symbols and so on but I understood it and that's all that mattered.

After stripping away the old switch and cutting a few wires, I wound up with two wires that when I put power through them lit up either the main beam or full beam. The wire with the yellow tape wrapped around it was the wire for the high beam. I found this out by using a light-up screwdriver and poking all the sockets behind the clocks, I eventually found one with power and using spare wire I had lying around I made a connection to each of the two wires - which lit up the bulbs.


Great. My plan was to make the electrics work as standard but without the low beam relay. Once I'd achieved that I'd put relays in to prevent any future problems.
The following colours of wires are from memory, so if you're undertaking this, ask questions and use the wiring diagram in the Haynes.
I got my new switchgear from a member on 400GB and using a continuity tester, I made a table of which cables did what. I eventually discovered that a black/red cable was delivering power to the switchgear and when the high beams were engaged, power (I think) came back down a white wire. I think I may of got colours/directions wrong as this was a month ago. This was how the switch worked that was bodged on;

I found another wire (blue maybe?) that had continuity to the power on sidelights being toggled. I ran a wire from these terminals in the left hand blocks to the two wires that led to my lights. Would you believe it, it worked! Now I had a basic working circuit without relays, I followed the Haynes book of lies schematic and wired in a relay (a quick nip to halfords to fetch two) using tape. Once confirmed it was working, I crimped on four spades and pushed them on the relay - then lathered it in tape and tucked it away. The relay is a bit big but you can't see it behind the fairings so who cares.
Now on the right side of the bike I found a big lump of tape, after unravelling it, I discovered four spades with connectivity to the left hand switch gear - looks like someone had an attempt at a high beam relay before but gave up maybe? Anyway, again with a continuity tester I discovered which wire had power back on the high beams being engaged and wired a relay using an online guide from 400GB. Rather than blow bulbs, I used my light-up screwdriver jammed in to a terminal on the back of the clocks, when I engaged high beams it lit up - I'd never had a working passing button either but even that worked!
I taped up the high beam relay and poked it in the frame as much as I could, it's hidden enough for me. As part of the bodge, a wire that should deliver power to the high beams DID come in to the block behind the clocks - but then when plugged in to the other terminal block it didn't go anywhere. So I cut the wire before it went in to the block behind the clocks and intercepted it with another cable. I ran this cable to that black wire with yellow tape from earlier. Works!
I taped everything up and tucked it all away as much as possible. It took me a few nights of tinkering and testing and writing down what colours and what terminals were doing what and when, but it was trial and error and I learned a LOT about electrics!

It all works now and has done for months, it could still do with a better tidy up behind the lights, but for now it'll do :)
Dan
A roaring V4 is the summer soundtrack.
- iDemonix
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- Posts: 651
- Joined: Tue Aug 24, 2010 10:26 pm
- Bike owned: '92 NC30
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Re: Dan's NC30
Someone on 125cc informed me it is a full system, cool.
After having them welded EVERYWHERE to ensure it'd never crack again, I think a hairline crack is developing near the can - again
I spotted it yesterday, if I fire her up today I'll put my hand round it and see if air is escaping, at the moment I'm hearing a ticking noise which is doing my head in;
http://www.youtube.com/watch?v=abl9r_mqgV4
The YouTube link ID ends in V4
Personally I think it might be from where the alu/steel/whatever plate around the exhausts meets the manifold (I've been calling it that for ages, it is a manifold right?) as there's a gap between the plate and the manifold - but I think this *may* be because I used gaskets that were slightly too tall. Had a word with a helpful member on 400GB (Rick / Pornodoguk) and he said he had a similar noise which turned out to be something loose in his clutch. I need to fix my clutch as it slips in almost every gear, I'm awaiting on the tools to arrive and I'm ordering a new set of friction plates + a gasket today.
Also, anyone in Nottingham want to come balance my carbs for me as I can't afford a carbtune
Bloody thing idles at 1400 one minute then the next it won't drop below 2000-2200 :/
After having them welded EVERYWHERE to ensure it'd never crack again, I think a hairline crack is developing near the can - again
http://www.youtube.com/watch?v=abl9r_mqgV4
The YouTube link ID ends in V4

Personally I think it might be from where the alu/steel/whatever plate around the exhausts meets the manifold (I've been calling it that for ages, it is a manifold right?) as there's a gap between the plate and the manifold - but I think this *may* be because I used gaskets that were slightly too tall. Had a word with a helpful member on 400GB (Rick / Pornodoguk) and he said he had a similar noise which turned out to be something loose in his clutch. I need to fix my clutch as it slips in almost every gear, I'm awaiting on the tools to arrive and I'm ordering a new set of friction plates + a gasket today.
Also, anyone in Nottingham want to come balance my carbs for me as I can't afford a carbtune
A roaring V4 is the summer soundtrack.
- iDemonix
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- Joined: Tue Aug 24, 2010 10:26 pm
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Re: Dan's NC30
Posty just brought me some goodies!

Torque wrench, which is that big it can double as a braker bar!
Rubber Mallet
Circlip Pliers
Knife
Clutch Removal Tool
Only thing is, I just tried to slot the clutch removal thing over my swingarm nut and it doesn't fit, it's a few mm too small - am I right in assuming that the swingarm nut and clutch nut are the same size? If so I'll need to have a word with the eBay seller and get a bigger one.

Torque wrench, which is that big it can double as a braker bar!
Rubber Mallet
Circlip Pliers
Knife
Clutch Removal Tool
Only thing is, I just tried to slot the clutch removal thing over my swingarm nut and it doesn't fit, it's a few mm too small - am I right in assuming that the swingarm nut and clutch nut are the same size? If so I'll need to have a word with the eBay seller and get a bigger one.
A roaring V4 is the summer soundtrack.
- iDemonix
- Site Supporter
- Posts: 651
- Joined: Tue Aug 24, 2010 10:26 pm
- Bike owned: '92 NC30
- Location: Banbury, Oxfordshire
Re: Dan's NC30
Think I've figured out the weird clicking noise - just as I thought it's another exhaust leak. Idk why I thought it was around the sides of the bike as it's leaking from near the can. I've called the welder up who previously welded my pipes, he didn't sound too happy to have me coming his way again haha.
I originally went to him to have two major cracks welded whilst the pipes were on the bike, I leaned the bike over and it pissed petrol all over his floor from the breather (I think). So this time I'm going to put about £2 in the bike as it's nearly empty and try get there without having to refuel! I'll see if he's got any vice grips so I can clamp the breather too.
Heading there this afternoon. When you lean an NC30, can anything else overflow pretty easily like oil or coolant?
Cheers,
Dan
I originally went to him to have two major cracks welded whilst the pipes were on the bike, I leaned the bike over and it pissed petrol all over his floor from the breather (I think). So this time I'm going to put about £2 in the bike as it's nearly empty and try get there without having to refuel! I'll see if he's got any vice grips so I can clamp the breather too.
Heading there this afternoon. When you lean an NC30, can anything else overflow pretty easily like oil or coolant?
Cheers,
Dan
A roaring V4 is the summer soundtrack.
-
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- iDemonix
- Site Supporter
- Posts: 651
- Joined: Tue Aug 24, 2010 10:26 pm
- Bike owned: '92 NC30
- Location: Banbury, Oxfordshire
Re: Dan's NC30
More goodies :D All were dirt cheap off eBay and all are pretty high quality! Sorry the picture is from bed, saturday morning hangover, rushed down to get them in my boxers, straight back to bed 



A roaring V4 is the summer soundtrack.
- iDemonix
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- Posts: 651
- Joined: Tue Aug 24, 2010 10:26 pm
- Bike owned: '92 NC30
- Location: Banbury, Oxfordshire
Re: Dan's NC30
If I hold a rag to the end of the can, it doesn't bog down much or cut out. Shit. I'm guessing I've still got a leak somewhere then, but I don't know if it's where the manifold meets the cylinder head or where the pipe meets the manifold. Agh. Doing my head in now, I'm flat out refusing to take the exhaust off ever again, it was the most fucking pain in the arse job ever.
Annoyed.
Annoyed.
A roaring V4 is the summer soundtrack.
- porndoguk
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Re: Dan's NC30
nice bike fella, its getting there nowiDemonix wrote:Someone on 125cc informed me it is a full system, cool.
Looks like standards Headers & a Yamamoto Rear with an aftermarket Viper Can
After having them welded EVERYWHERE to ensure it'd never crack again, I think a hairline crack is developing near the can - againI spotted it yesterday, if I fire her up today I'll put my hand round it and see if air is escaping, at the moment I'm hearing a ticking noise which is doing my head in;
Again Yamamoto have a habbit of cracking between the joints, mine have been welded up becuase of this
http://www.youtube.com/watch?v=abl9r_mqgV4
The YouTube link ID ends in V4
Personally I think it might be from where the alu/steel/whatever plate around the exhausts meets the manifold (I've been calling it that for ages, it is a manifold right?) as there's a gap between the plate and the manifold - but I think this *may* be because I used gaskets that were slightly too tall. Had a word with a helpful member on 400GB (Rick / Pornodoguk) and he said he had a similar noise which turned out to be something loose in his clutch. I need to fix my clutch as it slips in almost every gear, I'm awaiting on the tools to arrive and I'm ordering a new set of friction plates + a gasket today.
Thanks dude, it turned out to be 3 loose bolts on the starter clutch, but my bike still sometimes jams on start up and i still dont know why.
Also, anyone in Nottingham want to come balance my carbs for me as I can't afford a carbtuneBloody thing idles at 1400 one minute then the next it won't drop below 2000-2200 :/

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http://www.bikerstraining.com
Like us on Facebook for more information - First Bike on Scene - Emergency Response Skills - UK