View Full Version : Engine upsizing question
CookMySock
27th October 2009, 15:18
What is the situation if I buy a currently-registered and road-legal 250cc bike, and slap a 500cc engine in it? Obviously I will have to update the particulars with regard to the vehicle, but is there any recertification required, or any other hassles?
Add to that, adding larger brakes and different wheels and so on. Are there massive hoops to jump through with these sorts of modifications?
Many thanks,
Steve
The Pastor
27th October 2009, 16:12
nup no need to get it certified at all. just do it and give the cops the finger.
hayd3n
27th October 2009, 16:30
What is the situation if I buy a currently-registered and road-legal 250cc bike, and slap a 500cc engine in it? Obviously I will have to update the particulars with regard to the vehicle, but is there any recertification required, or any other hassles?
Add to that, adding larger brakes and different wheels and so on. Are there massive hoops to jump through with these sorts of modifications?
Many thanks,
Steve
you can try but it probably wont pass a wof
george formby
27th October 2009, 17:10
Unless things have changed, I remember CBR600 rolling chasis with 900cc fireblade motors rego'd & warranted as 600's. I guess it would come down to the usual thing, if nobody notices, nobody cares. Not sure what the repercussions would be if you were found out though. Fraudulent use of a bigger engine or maybe ACC levy fraud, hmmmm. Ok, $100 fine & a stern telling off.
CookMySock
27th October 2009, 17:13
Unless things have changed, I remember CBR600 rolling chasis with 900cc fireblade motors rego'd & warranted as 600's.Nah I wanted to keep it square and legal.
What can I get away with, and what needs to be certed and how?
Steve
PeeJay
27th October 2009, 17:30
What is the situation if I buy a currently-registered and road-legal 250cc bike, and slap a 500cc engine in it? Obviously I will have to update the particulars with regard to the vehicle, but is there any recertification required, or any other hassles?
Add to that, adding larger brakes and different wheels and so on. Are there massive hoops to jump through with these sorts of modifications?
Many thanks,
Steve
If you are a good little kiwi and dont wish to upset good order and disipline then by all means update the details, then you will be doing the recertification thing, engineers reports etc, etc, etc, and $$$$$$$$.
If you "believe" the replacement engine is exactly the same as the original you can try to use a MR16 to change the engine numbers in the rego details. Not sure who reads these, could be a smartarse who actually knows enough to send you a letter.
On the other hand you could just do it. The only official to look at it will be a wof guy, and if he asks, plead ignorant and say it has always been like that. You could even make sure the engine numbers match whats on the original rego details to prove it.
Of course I have no direct knowledge of this working, just something I heard on the internet.
If I ever feel I should kowtow/pay money to officialdom any more than necessary than I daresay I will update the details for a couple of my vehicles. I am sure there is a CEO of a government dept who needs a payrise in these tough times so we should all be doing our bit to keep their spirits/bank balances up.
meowmix
27th October 2009, 17:41
I don't have any actual evidence sorry, but for cars etc. that does require a re-cert, I would assume it is the same case with bikes.
The easiest way to do it would be to ring up the local certifier and ask them.
CookMySock
27th October 2009, 17:54
I don't have any actual evidence sorry, but for cars etc. that does require a re-cert, I would assume it is the same case with bikes.Yeah. I changed a seat in a van once, and ka-ching thats 400 bux thx mate. :pinch:
The easiest way to do it would be to ring up the local certifier and ask them.I guess. Traditionally I don't do that, coz I get their long detailed drawn-out method, rather than the simple way.
Someone on KB will have done it and got it legal. Maybe a trip down to the VTNZ office will pay dividends.
Steve
PeeJay
27th October 2009, 17:59
Nah I wanted to keep it square and legal.
What can I get away with, and what needs to be certed and how?
Steve
Any brake mods, a different engine, will need to be inspected by a Low Volume Vehicle inspector.$$$ This will lead to an engineers report to show your 250cc frame can handle 500cc of power. That the brakes are compatible, the bigger wheels arent going to upset the handling etc etc etc more $$$ Back to the LVV inspector to think about it.
As soon as you tell them anything there will be nothing to get away with. Once the process starts it cant be stopped apart from not doing anything at all.
Here are the people to talk to. http://www.lvvta.org.nz/
It isnt that bad but depending on what you are doing it can turn into a mission and cost time and money.
CookMySock
27th October 2009, 20:04
great. Oh well.
thanks anyway.
Steve
PeeJay
27th October 2009, 21:34
great. Oh well.
thanks anyway.
Steve
Dont let the Man keep you down
In the words Of NZ's preeminent contemporary filosifiser
Hey Doooug Jus do eet...... Leeev a leetle
imdying
28th October 2009, 13:38
Any brake mods, a different engine, will need to be inspected by a Low Volume Vehicle inspector.$$$ This will lead to an engineers report to show your 250cc frame can handle 500cc of power. That the brakes are compatible, the bigger wheels arent going to upset the handling etc etc etc more $$$ Back to the LVV inspector to think about it.
As soon as you tell them anything there will be nothing to get away with. Once the process starts it cant be stopped apart from not doing anything at all.
Here are the people to talk to. http://www.lvvta.org.nz/
It isnt that bad but depending on what you are doing it can turn into a mission and cost time and money.
great. Oh well.His post is correct, and as he says, it's not as bad as it sounds. The braking tests etc are fairly rudimentary, you should have no trouble. They don't charge an arm and a leg, and they don't charge extra based on the number of modifications.
vifferman
28th October 2009, 14:26
Huh.
Never even thought about this stuff when I had the Mutant XBR500RS. It was rego'd when I acquired it, so I just tidied it up, put it back on the road.
CookMySock
28th October 2009, 15:23
His post is correct, and as he says, it's not as bad as it sounds. The braking tests etc are fairly rudimentary, you should have no trouble. They don't charge an arm and a leg, and they don't charge extra based on the number of modifications.okies. If its just 400 bux then maybe I should just do it.
Huh.
Never even thought about this stuff when I had the Mutant XBR500RS. It was rego'd when I acquired it, so I just tidied it up, put it back on the road.Well maybe I'm overthinking it. This is why I'd start with a bike with current rego and wof. God help anyone who hacked something up from scratch and took it to be VINned.
Steve
imdying
28th October 2009, 16:00
Have a word with a low volume vehicle certifier, should be able to get a list from the LTNZ website. Generally they're older experienced mechanics who've been in the system since the Hot Rod Declaration days. The ones I have encountered are fair and reasonable, and passionate about modified vehicles, so it's not like they're going out of there way to fail you. There are odd things you will find that need doing, things like using the correct type of hose clips for fuel lines etc, but definitely nothing you can't handle if you're able to get the motor mounted in the first place!
IIRC it's about $400, which gets you your certification and a new VIN number, but you'll also need to pay for a WOF, and a minimum of 3 months registration to accompany the new plate you'll be issued.
Once that is done, it's a completely legitimate vehicle :yes:
/edit: My own thoughts are that if a vehicle can't pass the mechanical portions of the VIN compliance tests, then it's not suitable for road use in any case, they're not particularly stringent.
F5 Dave
28th October 2009, 16:08
okies. If its just 400 bux then maybe I should just do it.
Well maybe I'm overthinking it. This is why I'd start with a bike with current rego and wof. God help anyone who hacked something up from scratch and took it to be VINned.
Steve
erm I've done the last bit (see my thread on my 500). Yeah it wasn't too painful. the LVV certifier chap was sensible though so that eased things. He charged ~$400 as it happens. Then you get a huge plate that you need to site somewhere (seatbase is as good as any).
(Car based) rules are if the engine puts out 15% (from memory) more power it needs a LVV cert. All from LT website. Means you can put that 1600 in your old 1500 ford or whatever, but don't try slinging a twin turbo V8 in there without someone having a gander at it to see it isn't a total deathtrap. Fairly sensible idea I guess.
tigertim20
28th October 2009, 17:47
if i am remembering correctly, there is a section that states about modifying. if you can use the original mounting points, and factory brackets to mount it, it doesnt need a cert. as soon as you need to drill a single hole or make a new bracket, hello certification.
dont quote me on it though
riffer
28th October 2009, 18:04
FZR400 will take the 600 motor as a bolt-in replacement. This makes a nice little bike.
imdying
28th October 2009, 18:05
if i am remembering correctly, there is a section that states about modifying. if you can use the original mounting points, and factory brackets to mount it, it doesnt need a cert. as soon as you need to drill a single hole or make a new bracket, hello certification.No, you're incorrect.
FZR400 will take the 600 motor as a bolt-in replacement. This makes a nice little bike.A nice little bike which requires certification in New Zealand.
riffer
28th October 2009, 18:07
No, you're incorrect.
A nice little bike which requires certification in New Zealand.
Never said it didn't. However, it will be a safe bike. Kinda like a smaller 7/11 gixxer really.
F5 Dave
29th October 2009, 10:17
. . . All from LT website. . . .
Tiger, you are happy to offer all sorts of opinions but have you actually read the rules? It's all there, have a look before spouting what your mate at the pub said.
Here's a good start for those too lazy to google LTSA
http://www.ltsa.govt.nz/vehicles/modification/index.html
yes it's car based but bikes are covered too.
ScreaminGherkin
29th October 2009, 23:34
I do love how the certification threshold shedule lists Engine and Drivetrain under Miscellaneous Items.
Substitution of engines says it must be of equal power to what's being replaced or it needs a cert.
Modifications on the other hand let you go to 20% greater power.
awa355
30th October 2009, 10:36
Two things here, If modifications to the engine require certification? where do we stand with after market exhausts.
Also you can bet your bottam dollar, if these proposed rego fees come in, some germ in ACC will be looking out for this sort of thing.
imdying
30th October 2009, 10:45
The only thing you'll fit to an exhaust to make 20% more power is a turbo, they're fine.
F5 Dave
30th October 2009, 16:27
Again Awa did you read the sheet? It is pretty clear on exhausts & imdying is on the nail again.
jono035
1st November 2009, 08:50
If you're going to go for something that requires a low volume cert then it is definitely worth thinking about what else you might want to do at the same time and then have a chat with a few people about which low volume certifiers are reasonable, then have a chat with them about how they normally prefer to do things (what they want to see, when they want to see it etc.). That was the advice given to a friend who is doing some pretty heavy mods to an old car.
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