Are bigger carbs better?

[nzspokes]

Just mucking about looking at the spec of my GPZ400 and the same year 600. The 400 has 30mm carbs and the 600 has 32mm. Jet sizes etc are pretty much the same, even use the same needles.

So would running 32mm carbs on my 400 give me more power? Or will it kill an torque I have?

[pete376403]

If the ports dont match up to the bigger carb then its probably going to be a wasted effort. Maybe if the ports and valve sizes are increased it might do some good way up at the red line but low and midrange power might suffer accordingly.
I'm of the opinion that the engine designers usually know what they are doing.

[nzspokes]

Interestingly the rubber spacers between the carbs and head are the same part number.

[bogan]

No, bigger carbs will have a lower air velocity, therefore less vacuum through the venturi, which will prevent them from getting fully on the main jet. Which will then make em pretty hard to tune! And you would need to re-tune.

The only way (assuming both are tuned properly) carbs will give you more power, is if the offer significantly less flow restriction on the intake side, allowing more gas to enter the cylinders, as far as I'm aware, the intake length plays a bigger of a role in this than carb diameter.

[98tls]

If you do nothing else then theres little point,bit like those that spend big $ on an exhaust without doing anything else then more on rocking up to a dyno expecting a revelation.:killingmeTo stupid to be called idiots.:weird:

[nzspokes]

If you do nothing else then theres little point,bit like those that spend big $ on an exhaust without doing anything else then more on rocking up to a dyno expecting a revelation.:killingmeTo stupid to be called idiots.:weird:

My exhaust is far to big for the motor.

[bogan]

My exhaust is far to big for the motor.

So you'll be losing a bit of power there anyway. Stay with the current carbs, and if you want more power, do a proper tuned exhaust, then tune the carbs to suit, and maybe go to pods if your airbox is restrictive.

[nzspokes]

So you'll be losing a bit of power there anyway. Stay with the current carbs, and if you want more power, do a proper tuned exhaust, then tune the carbs to suit, and maybe go to pods if your airbox is restrictive.

I think my air box is fine apart from the inlet size. Ive removed the snorkel and thats given her more low end. I would like to try making the inlet bigger but would want to measure holes as its no point making the inlet bigger than the carb sizes. The exhaust is the exactly the same as the 600. Its got 4 into 2s with big cans but with a small outlet. If I was to change it I would go down to 1 good muffler.

I have been offered a full stainless Motad system out of a ZZR600 i think it is. He thinks it will fit but im not sure.

[FJRider]

Regardless of the size of the exaust or carb ... the fuel/air has to get past the valves .... and the trick to more power is getting more fuel/air past the valves when they are open (to get a bigger bang). Either by forced induction, enlarging the valves, or extending the length of time the valves are open.

[bogan]

I think my air box is fine apart from the inlet size. Ive removed the snorkel and thats given her more low end. I would like to try making the inlet bigger but would want to measure holes as its no point making the inlet bigger than the carb sizes. The exhaust is the exactly the same as the 600. Its got 4 into 2s with big cans but with a small outlet. If I was to change it I would go down to 1 good muffler.

I have been offered a full stainless Motad system out of a ZZR600 i think it is. He thinks it will fit but im not sure.

You might want the inlet a bit bigger than your carbs to account for more turbulence in the airbox, but position probably plays a part too, getting/removing resonances at different RPM.

Header diameter is not a bigger is better deal, you want the correct size to achieve the best air velocity at max RPM.

Rule of thumb calculation I've found online is: Area of Primary Pipe (sq in) = RPM × Cylinder Size (ci) ÷ 88,200
so 12000x6.1/88,200 gives 0.83 sq in, or .51in radius, or 26.1mm

Having 600 pipes will mean the gas travels at 2/3rds it optimal speed at max rpm, so your scavenging isn't going to work as it should; less flow velocity, is less flow inertia, is less new air pulled through, not to mention the effects from having the air column out of time for the header length.

This is why I laugh at the boyracers who put 3in exhausts on their mazda starlets and end up being passed by scooters and old men with zimmer frames. It's probably also the reason why there is the myth that backpressure is required for a motor to produce max power.

[nzspokes]

You might want the inlet a bit bigger than your carbs to account for more turbulence in the airbox, but position probably plays a part too, getting/removing resonances at different RPM.

Header diameter is not a bigger is better deal, you want the correct size to achieve the best air velocity at max RPM.

Rule of thumb calculation I've found online is: Area of Primary Pipe (sq in) = RPM × Cylinder Size (ci) ÷ 88,200
so 12000x6.1/88,200 gives 0.83 sq in, or .51in radius, or 26.1mm

Having 600 pipes will mean the gas travels at 2/3rds it optimal speed at max rpm, so your scavenging isn't going to work as it should; less flow velocity, is less flow inertia, is less new air pulled through, not to mention the effects from having the air column out of time for the header length.

This is why I laugh at the boyracers who put 3in exhausts on their mazda starlets and end up being passed by scooters and old men with zimmer frames. It's probably also the reason why there is the myth that backpressure is required for a motor to produce max power.

Problem is that they only made one system for the GPZ. 400/600 has the same. I could just run my system into one muffler, that wouldnt be hard to do. I may try lagging the pipes. It worked well on my honda.

[FJRider]

This is why I laugh at the boyracers who put 3in exhausts on their mazda starlets and end up being passed by scooters and old men with zimmer frames.

But ... the sound you hear from them is a cool echo ... that's gotta be worth another 1.5 Hp ... and doubles the value in parts of the car.

[bogan]

Problem is that they only made one system for the GPZ. 400/600 has the same. I could just run my system into one muffler, that wouldnt be hard to do. I may try lagging the pipes. It worked well on my honda.

yeh that should help, keeps the exhaust temp up, which raises the velocity, and opening up the muffler should do the same.


But ... the sound you hear from them is a cool echo ... that's gotta be worth another 1.5 Hp ... and doubles the value in parts of the car.

and if they use stainless pipe, it quadruples the value! have you seen how much the pay for stainless scrap metal now :bleh:

[nzspokes]

Only problem with lagging is the pipes start behind the radiator and the wrap makes my hands itch like a bastard even with gloves on.

[carburator]

the 30 in theroy will flow 82CFM the 32 97CFM

from experience I have a pair of 39FCR's on the bike
Ive had 41's FCR's on there ( tuned ) the 39's gave a better
range of power also better seat of the pants feel too.

better to have a broader range than try and live in a small powerband.

[bogan]

Only problem with lagging is the pipes start behind the radiator and the wrap makes my hands itch like a bastard even with gloves on.

Use the titanium stuff, don't need to wet wrap it, doesn't itch at all, and no need to spray it afterwards.

[nzspokes]

Use the titanium stuff, don't need to wet wrap it, doesn't itch at all, and no need to spray it afterwards.

I tred wet wrapping it and it works better dry. Didnt know there was a titanuim version.

[bogan]

I tred wet wrapping it and it works better dry. Didnt know there was a titanuim version.

There sure is http://www.designengineering.com/category/catalog/dei-cycle/motorcycle-exhaust-pipe-wrap-kits/titanium-exhaust-wrap-lr-technology and like most titanium things, it contains more awesome! But unlike most titanium things, its not hideously expensive.

[ducatilover]

I have been offered a full stainless Motad system out of a ZZR600 i think it is. He thinks it will fit but im not sure.
How much?
Measure up your GPZ port spacing and I'll measure my ZZR600 for you, but, I am pretty sure the ZZR600 has bigger ports than the GPZ.

As for the carbs, the ZZR400k motors used CVK-D32 carbs and the ZZR600 has 36s or something. I doubt the 32swould have any real power gains at all.

[nzspokes]

How much?
Measure up your GPZ port spacing and I'll measure my ZZR600 for you, but, I am pretty sure the ZZR600 has bigger ports than the GPZ.

As for the carbs, the ZZR400k motors used CVK-D32 carbs and the ZZR600 has 36s or something. I doubt the 32swould have any real power gains at all.

$450 and there brand new. hense my intrest. I will measure them over the weekend. I may leave wrapping untill Ive worked that out. I will need to pull the radiator to get in there.

[Akzle]

I'm of the opinion that the engine designers usually know what they are doing.
+1

+10 characters.

[Akzle]

I'm of the opinion that the engine designers usually know what they are doing.
+1

+10 characters.

[bogan]

+1

+10 characters.

You do realise the GPZ is made by Kawasaki right?

[nzspokes]

+1

+10 characters.

Yes they build motors to suit a market and emission standards.

But I dont care about emissions. I want powa.

[bsasuper]

You're wasteing $$ and time trying to get that motor to do anything more, either learn to ride it better, or get a more powerfull bike if you think you need it :yes: A well ridden 400 will keep up with a much bigger bike on the track.

[nzspokes]

You're wasteing $$ and time trying to get that motor to do anything more, either learn to ride it better, or get a more powerfull bike if you think you need it :yes: A well ridden 400 will keep up with a much bigger bike on the track.

Im not on the track. How do you know I cant find more? :shifty:

[pete376403]

The engine was designed for a certain role, meet certan standards and have a particular price point in its market. It would also be designed not to cannibalise other segments of the manufacturers market so it would be unlikely to have "extra power waiting to be easily unlocked" especially by backyard tuners.

As with just about any four stroke engine the cam, carb, compression route may gain some power at the top end, spinning the engine above the manufacturers design limits, but that comes at the expense of bottom / mid range (rideability) and engine life (the design criteria again.)

Just buy the 600. Or the ZX10

[nzspokes]

The engine was designed for a certain role, meet certan standards and have a particular price point in its market. It would also be designed not to cannibalise other segments of the manufacturers market so it would be unlikely to have "extra power waiting to be easily unlocked" especially by backyard tuners.



That sounds just like my Dad when I started stripping my 12a motor.

I learned him.......

[bsasuper]

Im not on the track. :


So why do you need to find more then?

[nzspokes]

So why do you need to find more then?

:facepalm:

[schrodingers cat]

Im not on the track. How do you know I cant find more? :shifty:

Just because you can doesn't mean you should.

The fact that you are HERE asking the questions tells me your knowledge base is too small to start with.
By all means spend the money as an investment is your own learning.
If you want more power the shortest path is a more cc.

[nzspokes]

Just because you can doesn't mean you should.

The fact that you are HERE asking the questions tells me your knowledge base is too small to start with.
By all means spend the money as an investment is your own learning.
If you want more power the shortest path is a more cc.

Tuff crowd.

Thought was a motorcycle website, not a granny one.

[ktm84mxc]

A man always needs more power it's his God given rite, there's a easy route or the less traveled harder route by tinkering\modifying the bike.
The main handicap with the GPZ400 is the bike runs all the fitments of the 600 with 33% less motor it will always be a struggle to get to perform up to a late model RVF\CBR\ZXR\FZR 400 spec.
It could be done at a cost of time and money , just think you're Bert Munro beavering away in your shed paying homage to the "Gods of Speed" .

[schrodingers cat]

Tuff crowd.

Thought was a motorcycle website, not a granny one.

I get it now. Its a quiz.

You ask the question and we supply the answer you want to hear

[nzspokes]

A man always needs more power it's his God given rite, there's a easy route or the less traveled harder route by tinkering\modifying the bike.
The main handicap with the GPZ400 is the bike runs all the fitments of the 600 with 33% less motor it will always be a struggle to get to perform up to a late model RVF\CBR\ZXR\FZR 400 spec.
It could be done at a cost of time and money , just think you're Bert Munro beavering away in your shed paying homage to the "Gods of Speed" .

You get it. The 400 is quite a bit lighter than the 600 as it has and alloy frame over a steel one etc.

I have been known to spend all night porting motors......

[bogan]

Does that mean the 400 internals are all over-engineered? There's only one thing to do with over-engineered internals...

264097

[nzspokes]

Does that mean the 400 internals are all over-engineered? There's only one thing to do with over-engineered internals...

264097

Took me a while to get what you meant, just saw the car in the background.

gotta love over engineering.

[GrayWolf]

Just mucking about looking at the spec of my GPZ400 and the same year 600. The 400 has 30mm carbs and the 600 has 32mm. Jet sizes etc are pretty much the same, even use the same needles.

So would running 32mm carbs on my 400 give me more power? Or will it kill an torque I have?

probably one of the best 'parts bin specials' that answers the question was Kawasaki's own ZL1000 eliminator from the 1980's. It was Kwak's 'answer' to the V-max, Madura, and Magna 'Power cruisers'. Apart from the frame the bike was a part bin special....GTR1000 shaft drive bottom end (beefed up shaft) GPZ900 close ratio 6 speed box, ZX10 top end, but GPZ 900 head (valves) and GPZ900 carbs (both smaller than the ZX10 ones)... The cam? I guess could only be described as the GTR cam with GPZ lift. I owned one of these and they were quicker to 50mph than the V-max, (we are talking fraction of seconds). All those bike produced almost as much torque as a sprot bike at full power, at almost 1/3 of the rpm. Then literally doubled torque every 3000rpm and BHP was almost a 45 degree climb regards to revs. At only 110bhp (sprot bikes were about 125-130bhp then) the bike would pull in top gear from 1500rpm with gentle throttle in top. The smaller carbs will give you better low/mid range power, the bigger carbs if everything else is 'right' will give more fuel/air at higher RPM.
At the end of the day, they old saying is true,, no substitute for 'cubes'

[nzspokes]

probably one of the best 'parts bin specials' that answers the question was Kawasaki's own ZL1000 eliminator from the 1980's. It was Kwak's 'answer' to the V-max, Madura, and Magna 'Power cruisers'. Apart from the frame the bike was a part bin special....GTR1000 shaft drive bottom end (beefed up shaft) GPZ900 close ratio 6 speed box, ZX10 top end, but GPZ 900 head (valves) and GPZ900 carbs (both smaller than the ZX10 ones)... The cam? I guess could only be described as the GTR cam with GPZ lift. I owned one of these and they were quicker to 50mph than the V-max, (we are talking fraction of seconds). All those bike produced almost as much torque as a sprot bike at full power, at almost 1/3 of the rpm. Then literally doubled torque every 3000rpm and BHP was almost a 45 degree climb regards to revs. At only 110bhp (sprot bikes were about 125-130bhp then) the bike would pull in top gear from 1500rpm with gentle throttle in top. The smaller carbs will give you better low/mid range power, the bigger carbs if everything else is 'right' will give more fuel/air at higher RPM.
At the end of the day, they old saying is true,, no substitute for 'cubes'

I agree, "theres no replacement for cubic displacement"

Im lookin at pulling the trigger on a Bandit next week anyway. Its only 800cc bigger.....

[FJRider]

I agree, "theres no replacement for cubic displacement"

Im lookin at pulling the trigger on a Bandit next week anyway. Its only 800cc bigger.....

In the tight and twisty's ... the 400 will still be quicker ...

Having the power is good ... but you need to be able to use it. Skill to use it to the best advantage comes later.

[bsasuper]

:facepalm:

No problem asmokies

[DEATH_INC.]

Just do it. ANYTHING can be made to make more power. And more is better. Bigger carbs, bigger cams, better exhaust, a bit (or a lot) of grinding in the ports and chambers, and a bit more compression. Get into it!
No harm in spending a bit of time and money making what you've got go better. :headbang:
Any idiot with a cheque book can buy something faster :yawn: but where's the fun in that.

[GrayWolf]

Just do it. ANYTHING can be made to make more power. And more is better. Bigger carbs, bigger cams, better exhaust, a bit (or a lot) of grinding in the ports and chambers, and a bit more compression. Get into it!
No harm in spending a bit of time and money making what you've got go better. :headbang:
Any idiot with a cheque book can buy something faster :yawn: but where's the fun in that.

If the bike was a 'keeper' apart from the power? Maybe that would be an option. But at the end of the day you spend $X000 on tuning bits for a bike that wont be worth the extra $X000 at the end of the exercise, has had its reliability and longevity possibly compromised by the level of tune, only to still be out performed by a bigger bike that would have likely only cost the $X000 to begin with.

[ducatilover]

In the tight and twisty's ... the 400 will still be quicker ...

Having the power is good ... but you need to be able to use it. Skill to use it to the best advantage comes later.
The GPZ isn't exactly a wonderful handling bike anyway...:msn-wink:

Just do it. ANYTHING can be made to make more power. And more is better. Bigger carbs, bigger cams, better exhaust, a bit (or a lot) of grinding in the ports and chambers, and a bit more compression. Get into it!
No harm in spending a bit of time and money making what you've got go better. :headbang:
Any idiot with a cheque book can buy something faster :yawn: but where's the fun in that.
:banana: This guy rules.

[ducatilover]

If the bike was a 'keeper' apart from the power? Maybe that would be an option. But at the end of the day you spend $X000 on tuning bits for a bike that wont be worth the extra $X000 at the end of the exercise, has had its reliability and longevity possibly compromised by the level of tune, only to still be out performed by a bigger bike that would have likely only cost the $X000 to begin with.
All I can say is, if we all followed that logic we'd e riding ZZR1400s.
Who gives a turtles flipper if something is faster and cheaper? When modifying anything logic and economics is thrown out the window
Should I have not built my bike? :cool: I could've got a much "better" bike for the same money.

[FJRider]

The GPZ isn't exactly a wonderful handling bike anyway...:msn-wink:

Often in the rebuild of older bikes ... standard (or similar) suspension is fitted. A sensible upgrade with modern equipment wont give a speed increase ... but you wont need to go as slow as you did ...

Often the chase for better handling is more productive in terms of point A to point B times ... than the search for more power.

[bogan]

Often in the rebuild of older bikes ... standard (or similar) suspension is fitted. A sensible upgrade with modern equipment wont give a speed increase ... but you wont need to go as slow as you did ...

Often the chase for better handling is more productive in terms of point A to point B times ... than the search for more power.

And it's the suspension that has been rather static over the years. They need to compress the development time right down, and start rolling out bikes with proper bits on em.

Or just take your money, and bounce back a decade or two, spend a little on the bike, a little on the suspenders, then spring well ahead of the 'newer' crap!

We may be getting a bit off-line with regard to the original question now...

[nzspokes]

I think a major point missed here is the are people like myself that enjoy pulling these things apart to see how they tick. The enjoyment comes from the work as well as the use. :cool:

[ktm84mxc]

Yes sir re trying to up grade a older bike is a plan of self grow and applied knowledge gained through trial and error.
First of try shedding some weight from the GPZ eg exhaust, lighter wheels, pilllon pegs[ if not needed], tail tidy etc . Fairing lowers can also go if you want the rat look.
Second get into the air box open it up fit a K&N style filter, pods are great but have been known to cause stuck slides in the rain. FCR style carbs, Head mods, REprofiled cams, High comp pistons etc depends on your budget.
A well ridden 400 can stay with most bikes in the twisties only loosing on the longer straights.
A Bandit 1200 is the classic UJM a bike to fit every ones needs to a point.

[DEATH_INC.]

If the bike was a 'keeper' apart from the power? Maybe that would be an option. But at the end of the day you spend $X000 on tuning bits for a bike that wont be worth the extra $X000 at the end of the exercise, has had its reliability and longevity possibly compromised by the level of tune, only to still be out performed by a bigger bike that would have likely only cost the $X000 to begin with.
WTF has money got to do with it????? Who give a flying f**k if it costs way more than it's worth? Heaps of people buy new bikes even though you lose a bundle on em.....think about that for a bit....
If you don't get the idea of modding something, then you probably never will. It's not really about the money, or even the performance, it's like Burt said in the movie "it's in the doing of it"

[GrayWolf]

WTF has money got to do with it????? Who give a flying f**k if it costs way more than it's worth? Heaps of people buy new bikes even though you lose a bundle on em.....think about that for a bit....
If you don't get the idea of modding something, then you probably never will. It's not really about the money, or even the performance, it's like Burt said in the movie "it's in the doing of it"

The point IS the bike ISN'T a keeper, so a waste of time and money to work on more power.... if he doesn't think the bike is ideal in all aspects apart from the power.. why WASTE the dosh on it? Think about that for a bit??

[bogan]

The point IS the bike ISN'T a keeper, so a waste of time and money to work on more power.... if he doesn't think the bike is ideal in all aspects apart from the power.. why WASTE the dosh on it? Think about that for a bit??

Its about making the most of what you have. Spend 1k to improve your ride for the next year, or put up with it and save 8k for a newer bike, then spend 1k improving that. Why wait, when the cheapest option for a better bike now, will usually be to modify you current one. Who knows, maybe you'll be like me and end up with a 5k bike worth more than any of the newer bikes that come with 4x the price tag.
And then there is still the 'doing it' argument you don't seem to get.

[DEATH_INC.]

The point IS the bike ISN'T a keeper, so a waste of time and money to work on more power.... if he doesn't think the bike is ideal in all aspects apart from the power.. why WASTE the dosh on it? Think about that for a bit??

It's only money. Who cares?

[GrayWolf]

Its about making the most of what you have. Spend 1k to improve your ride for the next year, or put up with it and save 8k for a newer bike, then spend 1k improving that. Why wait, when the cheapest option for a better bike now, will usually be to modify you current one. Who knows, maybe you'll be like me and end up with a 5k bike worth more than any of the newer bikes that come with 4x the price tag.
And then there is still the 'doing it' argument you don't seem to get.

Hmm let me see..... Suzuki AP50 with an AS100 hop up (moped rules in the UK) RD250 hop up to 350, RD250-RD400, hop up with extra fin removed and 250cc stamped on barrells, re stamped engine cases (I was trained as a toolmaker :cool:) RD 350LC Stevens tuned, uprated brakes, Micron pipes, Ace bars etc, etc.
Nope your right, I dont have an effing clue what your talking about....
What I DO know is, having moved up to larger capacity machines, the 'need' to modify for performance reduced. Maybe in direct relation to the fact the bikes were not cheapo S/hand ones but generally only a few years old or new. Regardless of tuning and improving the GPz400 is an 'old bike' and a more modern 600 would offer a substantial improvement on performance and frame technology for about the same price as the sale of the 400 plus the 1-2k he could spend on the 400 improving it.
As I have said so many ruddy times the 'need for speed' from this years XYZRD1500vkr superturbocrotchrocket, or; tuning an older bike to perform as well or better for speed 99% of the time is NOT ability driven. Its simply EGO driven, "I have and ride the 'shizzz' so my nuts are bigger than yours". Reality is, a good rider will outrun an average rider on a bike with substantially more power due to ABILITY. A sprot 600cc will perform in hard riding, beyond the ability of 95% of riders on the road.

Disclaimer: I will also admit that the 'average' brain out no thought of life or limb 'crotch jockey' can often outrun most other riders due to complete and utter disregard for roadcraft, safety of self and/or others... there's plenty of those out there too.

[bogan]

Again, modding for the fun of it, and the sense of achievement gained from improving something is a good enough reason. I would have thought with your list of modded bikes you would understand that...
Maybe the GPZ is old enough to be a lost cause for some, but seems like it isn't for others.

[GrayWolf]

Again, modding for the fun of it, and the sense of achievement gained from improving something is a good enough reason. I would have thought with your list of modded bikes you would understand that...
Maybe the GPZ is old enough to be a lost cause for some, but seems like it isn't for others.

The difference is to my mind, uprating modern bikes is an extremely expensive affair for a minimal to moderate return. The old bikes I played with, were mostly easy and simple head, barrel and piston swaps. The RD400 conversion, the motor was a straight bolt in with no plates or offsetting required. Brakes across the ranges were fairly standardised... Even a simple forks or wheel change/swap these days is a bloody minefield. The bikes themselves were in a much lower state of tune than even the GPz400 we're referring to, so the tuning was more 'effective' for the cost involved.

Reading the OP's post, he isnt considering doing it as an exercise of love, its a stop gap, which for the cost of performing the upgrades? PLus the bike could be higher miliage which brings on some other 'issues' possibly with the upgrade. I will still stand by saying sell the 400 and put the 1-2k he'll spend, on a mid 90's onwards 600cc.

[schrodingers cat]

Bogan,
you presume the OP is geared to learn from the experience.
Tee throwaway 'I learned my Dad with my 12A' (and other comments) suggests he isn't.

Others appear to be able to see an alternative view. Think about that for a bit

[bogan]

Bogan,
you presume the OP is geared to learn from the experience.
Tee throwaway 'I learned my Dad with my 12A' (and other comments) suggests he isn't.

Others appear to be able to see an alternative view. Think about that for a bit

I would think that the other threads hes posted up, and previous work he has done, suggests he does learn from the experience, and enjoys the experience. And since its his bike, his view is the only one that matters. Think about that for a bit :bleh:

Anyway, when did we stop discussing the best way to supercharge it? I reckon the clutch side cover could be modified so the supercharger runs off the crankshaft primary drive gear. Thus mounting the supercharger in front of the engine. Of course this would mean moving the headers, I think a scrambler pipe setup for each side would be brilliant.

[nzspokes]

Bogan,
you presume the OP is geared to learn from the experience.
Tee throwaway 'I learned my Dad with my 12A' (and other comments) suggests he isn't.

Others appear to be able to see an alternative view. Think about that for a bit

Well champ, I just got home from a morning blasting around on an 82 XR200. I got that bike for $400 with a stuffed motor. Why would I do that when Ive never pulled a motor cycle engine apart? Because I wanted to learn how to. So I got a manual and got amazing advice on this site. The bikes still old and ugly but is huge fun on Trail rides.

My Dad told me getting an old RX7 S1 was a waste of time and get something more modern. I learned how to rebuild the motor and bridged it. I raced that car in club events.

The CBX250 I started riding on was in rough shape when I got it. And at one stage it refused to run. But with advice from this site I got it running and rode it from auck to the cape and other adventures for 13000k. And by the end it gave modern 250s a good nudge.

There are many other projects ive had and had fun with.

All of that is from learning. So please tell me what is wrong with that?

[ducatilover]

I would think that the other threads hes posted up, and previous work he has done, suggests he does learn from the experience, and enjoys the experience. And since its his bike, his view is the only one that matters. Think about that for a bit :bleh:

Anyway, when did we stop discussing the best way to supercharge it? I reckon the clutch side cover could be modified so the supercharger runs off the crankshaft primary drive gear. Thus mounting the supercharger in front of the engine. Of course this would mean moving the headers, I think a scrambler pipe setup for each side would be brilliant.
Nah, put the blower pulley out the stator side, would be easy enough to make a shaft that bolts on to the flywheel/crank bolt with a pulley on the end :banana:


Thought I'd add, I spent another whole day playing with both my bikes, which are apparently too old and shit to bother with. I challenge any to who think so to present a better bike they've built :bleh:

[mossy1200]

Took me a while to get what you meant, just saw the car in the background.

gotta love over engineering.

Wow. Shes so hot the car has an erection.

[GrayWolf]

Nah, put the blower pulley out the stator side, would be easy enough to make a shaft that bolts on to the flywheel/crank bolt with a pulley on the end :banana:


Thought I'd add, I spent another whole day playing with both my bikes, which are apparently too old and shit to bother with. I challenge any to who think so to present a better bike they've built :bleh:

I'll repeat this again.. they are labour's of 'love'.. so worthwhile to you. The OP is purely looking at the work to make a 'stop gap' machine. Hence why I would say sell the 4 hundy put the 1-2k alongside the cash it sells for and buy a mid 90's onwards 600

[nzspokes]

I'll repeat this again.. they are labour's of 'love'.. so worthwhile to you. The OP is purely looking at the work to make a 'stop gap' machine. Hence why I would say sell the 4 hundy put the 1-2k alongside the cash it sells for and buy a mid 90's onwards 600

Where did the 1/2k cash come from? You giving it to me?

So what apart from motor makes a 90s bike better?

[bogan]

Nah, put the blower pulley out the stator side, would be easy enough to make a shaft that bolts on to the flywheel/crank bolt with a pulley on the end :banana:

Thought I'd add, I spent another whole day playing with both my bikes, which are apparently too old and shit to bother with. I challenge any to who think so to present a better bike they've built :bleh:

Whats the strength like at that end though? Actually speaking of which, have you seen the RC31s which put extra crank bearings on the cases, fucking crazy cool!

The definitely a few around which could give you a run for your money... and its def the old one which have more class!

[ducatilover]

Where did the 1/2k cash come from? You giving it to me?

So what apart from motor makes a 90s bike better?
Brakes :cool: mine has great brakes.

[nzspokes]

Brakes :cool: mine has great brakes.

And does good wheelies?

[ducatilover]

Whats the strength like at that end though? Actually speaking of which, have you seen the RC31s which put extra crank bearings on the cases, fucking crazy cool!

The definitely a few around which could give you a run for your money... and its def the old one which have more class!
You have access to a welder, just make a huge fuck off crank brace :2thumbsup
Extra crank bearings? That's pretty intense, got link? :cool:
My bike's the bestest ever

[bogan]

Brakes :cool: mine has great brakes.

And USD, oh wait, though it was only briefly with the stockers, more permanent now :D


You have access to a welder, just make a huge fuck off crank brace :2thumbsup
Extra crank bearings? That's pretty intense, got link? :cool:
My bike's the bestest ever

lol, and I wouldn't need to put parts in the vibration polisher then, the unblanced crank would shake everything smooth while on the bike!

Nah, the forum is down again.

[ducatilover]

Well, there we have it; a plan for you spokey.
Keep teh GPZ.
600 motor.
ZXR forks, wheels and L model swing arm.
6 piston brakes from a ZRX400 (bolt right on to ZXR forks)
Supercharger.

Sorted :banana:

[nzspokes]

Well, there we have it; a plan for you spokey.
Keep teh GPZ.
600 motor.
ZXR forks, wheels and L model swing arm.
6 piston brakes from a ZRX400 (bolt right on to ZXR forks)
Supercharger.

Sorted :banana:

We shall see what happens this week as to what way I will go. See if I can make this Bandit deal work.

Then Bandit mods will start.............:drool:

[ducatilover]

You'll be happy to know that Bandits are an epic platform to mod.
They loooooove some forced induction

[pete376403]

Well champ, I just got home from a morning blasting around on an 82 XR200. I got that bike for $400 with a stuffed motor. Why would I do that when Ive never pulled a motor cycle engine apart? Because I wanted to learn how to. So I got a manual and got amazing advice on this site. The bikes still old and ugly but is huge fun on Trail rides.

My Dad told me getting an old RX7 S1 was a waste of time and get something more modern. I learned how to rebuild the motor and bridged it. I raced that car in club events.

The CBX250 I started riding on was in rough shape when I got it. And at one stage it refused to run. But with advice from this site I got it running and rode it from auck to the cape and other adventures for 13000k. And by the end it gave modern 250s a good nudge.

There are many other projects ive had and had fun with.

All of that is from learning. So please tell me what is wrong with that?

Spokes, without meaning to belittle your efforts (and damn good on you for trying; Munro, Britten, etc never took no for an answer either) you describe rebuilding an XR200 following factory supplied instructions, so thats not really modifying.

The rotary, well there is a huge wealth of information about making them perform, so again, thats really just following instructions.

The 400 - because of what it is, no-one has really bothered with them much so the information isn't available. Being right at the very leading edge of discovery tends to be both expensive and dissappointing.

OTOH, make your 400 into something that will almost keep up with 600s and I'll be the first to applaud.

[nzspokes]

Spokes, without meaning to belittle your efforts (and damn good on you for trying; Munro, Britten, etc never took no for an answer either) you describe rebuilding an XR200 following factory supplied instructions, so thats not really modifying.

The rotary, well there is a huge wealth of information about making them perform, so again, thats really just following instructions.

The 400 - because of what it is, no-one has really bothered with them much so the information isn't available. Being right at the very leading edge of discovery tends to be both expensive and dissappointing.

OTOH, make your 400 into something that will almost keep up with 600s and I'll be the first to applaud.

Tough crowd.

XR. Not modded apart from some porting. But had never done one before. So learning.

Rotary, Ran it bridge with holley. I didnt have a manual for it. So learning.

I ported a 2l Pinto motor from an american manual. Had not done one before so learning.

400 would just be a tuning exercise. So the basics are not that hard. Decent exhaust and tune carbs. I guess for some thats a big deal.

Im not trying to beat anything. I keep up fine with the people I ride with.

I just enjoy the process.

So I dont get the problem, why is reading manuals and learning a problem?

[bogan]

So I dont get the problem, why is reading manuals and learning a problem?

I guess some just do repairs from a manual by following the steps, without the curiosity or aptitude to think about why and how the parts work.
"The service manual is no more than a cook book. It is a good reference to a chef, but a lousy textbook for a novice."

[nzspokes]

Soooo, hows got some Bandit mod ideas.......

[bogan]

Soooo, hows got some Bandit mod ideas.......

What year/size?

[nzspokes]

K1 (2001) 1200.

Found the justBandits.com site. Bike already has some mods from this site. Braded lines, smaller front sprocket, engine bars etc

[bogan]

Fuck, and I thought doug's CB400 was beige :bleh:

Have to do something about that exhaust, looks like plenty of clearance for an under engine one. Using a turbo means the mid pipe length isn't going to affect the tune either, so short is good. Not really sure where the intercooler will go, maybe go with a small laser headlight in the center of the original headlight bucket, and use the extra area for a ram air system, and make the intecooler part of the intake manifold that way. Make up a bigger tail unit to hold the fuel, and shift all the electronics and battery to the top of the (now false) fuel tank. Biff that fugly swingarm and put a single sided one on there, pipe style ducati one would look good, with some cazzo wheels also. While you're swapping the front wheel you may as well go for some USD forks, MV use some pretty beefy ones.

Thats good for starters, I can probably think of some more stuff if you need...

[nzspokes]

Fuck, and I thought doug's CB400 was beige :bleh:

Have to do something about that exhaust, looks like plenty of clearance for an under engine one. Using a turbo means the mid pipe length isn't going to affect the tune either, so short is good. Not really sure where the intercooler will go, maybe go with a small laser headlight in the center of the original headlight bucket, and use the extra area for a ram air system, and make the intecooler part of the intake manifold that way. Make up a bigger tail unit to hold the fuel, and shift all the electronics and battery to the top of the (now false) fuel tank. Biff that fugly swingarm and put a single sided one on there, pipe style ducati one would look good, with some cazzo wheels also. While you're swapping the front wheel you may as well go for some USD forks, MV use some pretty beefy ones.

Thats good for starters, I can probably think of some more stuff if you need...

LOL, its already got a can that will wake the neighbors in the morning.

[bogan]

There a lot more to an exhaust that just decibels fulla.

[bogan]

There a lot more to an exhaust that just decibels fulla.

In fact, the mark of a great exhaust, is sounding awesome but doing so quietly.

[ducatilover]

Fuck, and I thought doug's CB400 was beige :bleh: RetroBeige, it's the in thing bro


Have to do something about that exhaust, looks like plenty of clearance for an under engine one. Using a turbo means the mid pipe length isn't going to affect the tune either, so short is good. Not really sure where the intercooler will go, maybe go with a small laser headlight in the center of the original headlight bucket, and use the extra area for a ram air system, and make the intecooler part of the intake manifold that way. Make up a bigger tail unit to hold the fuel, and shift all the electronics and battery to the top of the (now false) fuel tank. Biff that fugly swingarm and put a single sided one on there, pipe style ducati one would look good, with some cazzo wheels also. While you're swapping the front wheel you may as well go for some USD forks, MV use some pretty beefy ones.

Thats good for starters, I can probably think of some more stuff if you need...
There are heaps of 180whp+ turbo Bandit 12s not running coolers. If you run low enough boost and don't advance the timing and get the venting to the carb bowl right, it'll run 6-7psi with detonation on standard jetting and no intercooler :D

To my knowledge the easiest ways to get powaaaaaaaah from a Bandit is in the head, from memory you can use cams from another 'zuki, either RF9 or GSX-R11 (I think, google will help)

Probably the cheapest and easiest Jap bike to get big bore kits for.

There are countless swing arm conversions/mods out there, google again.

And about a million options for fork upgrades
Even some really nice aftermarket seats to get it ridiculously comfy too.

The Bandit is awesome for modifying, anything you can think of has been done. Even a twincharged one...

[bogan]

There are heaps of 180whp+ turbo Bandit 12s not running coolers. If you run low enough boost and don't advance the timing and get the venting to the carb bowl right, it'll run 6-7psi with detonation on standard jetting and no intercooler :D

To my knowledge the easiest ways to get powaaaaaaaah from a Bandit is in the head, from memory you can use cams from another 'zuki, either RF9 or GSX-R11 (I think, google will help)

Probably the cheapest and easiest Jap bike to get big bore kits for.

There are countless swing arm conversions/mods out there, google again.

And about a million options for fork upgrades
Even some really nice aftermarket seats to get it ridiculously comfy too.

The Bandit is awesome for modifying, anything you can think of has been done. Even a twincharged one...

yeh, but I can fart more than 6psi, gotta do these things properly!
Maybe put a drag swingarm on instead of an SSSA, with a big turbo, and aircooled, it'll be mint down the strip!

[ducatilover]

yeh, but I can fart more than 6psi, gotta do these things properly!
Maybe put a drag swingarm on instead of an SSSA, with a big turbo, and aircooled, it'll be mint down the strip!
Wait...less wheelies? :(:weep:

[bogan]

Wait...less wheelies? :(:weep:

nah, drag swingarms are longer, so you do higher wheelies :eek:

[nzspokes]

In fact, the mark of a great exhaust, is sounding awesome but doing so quietly.

Its a scorpion one. Its nice but not droning.

I need to get used to not changing gears.

[nzspokes]

Wait...less wheelies? :(:weep:

A wheelie has been done. Not intentionally.

[ducatilover]

:headbang: Never thought of it that way