Performance mods on pre gen

[Rollingmenace]

Ok other than the basics like pod filters and exhaust.. What options are out there to boost performance in a pre gen motor... Pistons, cams, head work Ect... I'm trying to get most out of motor without sacrificing reliability... How about sources.. Any members here do this type of work ... Give me some options .. Thanks

[Jesse8931]

Best performance mod you can do is become a better rider.

ss brake lines and good tires will be way better then anything else you do to the bike.

[Motofool]

http://faq.ninja250.org/wiki/Bike_mods_for_beginners

http://faq.ninja250.org/wiki/Why_per...e_good_for_you

http://faq.ninja250.org/wiki/Can_I_i...ole_jet_kit%3F

http://faq.ninja250.org/wiki/Battery...r_carb_removal

http://faq.ninja250.org/wiki/I_want_...uretor_jetting

[Lychee]

Given the extensive bike list I wonder if the OP is a veteran.

If so, a good question would be what will be the planned usage of the motorcycle?

[Motofool]

Originally Posted by Lychee

Given the extensive bike list I wonder if the OP is a veteran.
........

According to his first post, he has been riding for 29 years.

Originally Posted by Rollingmenace

hello all
My name is Zach im new to the ninja scene but have been riding about 27 years .. i own a whole slew of bikes quads and atc's.. i just acquired a 96 Ninja 250............

[Rollingmenace]

Thanks for the links fool.. Ill check them out ...

As far as usage I picked up a few motors the other day one to replace the one I shelled in the ninja ... The other is going to be for a project I'm going to make a street tracker out of .... Similar to this one pictured.

Mainly used for commuting around town but I may take it up and actually put some time in at the dirt track.. Possibly even hit the ice with it... So I want to really squeeze all the hp I can out of the motor I'm aware of the basics filters pipes jetting ect but I'm looking to really try and maximize hp ... Pistons ,cams ,head work ,back cut gears ect. Is there stuff on the market for this and is the gain worth the cost... And I still want to run on pump gas

I do have plenty rider experience .. Lol .. Like fool said been riding almost 30 years I have rode and raced everything with 2 3 and 4 wheels on pavement dirt and ice ... I've held mra licenses .. I currently been running quad c class colorado off road championship series... I ice race 2-3-4 wheels. 2008 colorado state ice racing champ novice bare tire class... And I leave Wednesday with a load of vintage ATC's (three wheelers) headed for Utah to hit the dunes and then to Idaho in June.... Plenty of experience here and that being said still learn new stuff every time I head out

[rabies]

oooooh i likey....

[rabies]

i was about to make the same thread.
i have an 04 pregen. not to thread jack. very relative.
what is the std bore for our motors? 62mm? and compression?
i see some 66mm 13.1 pistons on ebay. might have to do E85 or 93 octane though.
cams? having trouble finding sellers and parts.
iv built motors for cars before. bike stuff couldnt be harder.

take apart and clean
take to shop,
have them bore and hone to pistons you bring them.
new gaskets, oil pump, chain tensioner, chain.
reassemble with new bearings and rings.
assemble, tune carbs to match, brap brap

[EMSRacer07]

Originally Posted by Rollingmenace

Thanks for the links fool.. Ill check them out ...

As far as usage I picked up a few motors the other day one to replace the one I shelled in the ninja ... The other is going to be for a project I'm going to make a street tracker out of .... Similar to this one pictured.

Mainly used for commuting around town but I may take it up and actually put some time in at the dirt track.. Possibly even hit the ice with it... So I want to really squeeze all the hp I can out of the motor I'm aware of the basics filters pipes jetting ect but I'm looking to really try and maximize hp ... Pistons ,cams ,head work ,back cut gears ect. Is there stuff on the market for this and is the gain worth the cost... And I still want to run on pump gas

I do have plenty rider experience .. Lol .. Like fool said been riding almost 30 years I have rode and raced everything with 2 3 and 4 wheels on pavement dirt and ice ... I've held mra licenses .. I currently been running quad c class colorado off road championship series... I ice race 2-3-4 wheels. 2008 colorado state ice racing champ novice bare tire class... And I leave Wednesday with a load of vintage ATC's (three wheelers) headed for Utah to hit the dunes and then to Idaho in June.... Plenty of experience here and that being said still learn new stuff every time I head out

Guy that made that bike you have pictured was from here in AZ. He was selling it, not sure anymore but he had it for sale for like 1k. I checked it out it was really nice but not really street legal.

[Motofool]

Originally Posted by Rollingmenace

Thanks for the links fool.. Ill check them out ...
Mainly used for commuting around town but I may take it up and actually put some time in at the dirt track.. Possibly even hit the ice with it... So I want to really squeeze all the hp I can out of the motor I'm aware of the basics filters pipes jetting ect but I'm looking to really try and maximize hp ...

You are welcome, Zach

For those purposes, and unless you will try for 105 mph commuting around town, on dirt and on ice, you may want to consider gaining torque at the expense of final speed via a bigger rear sprocket (may need a new, longer chain).

[Lychee]

From the wikipedia:

Bore and Stroke 62.0 mm × 41.2 mm (2.44 in × 1.62 in)
Compression Ratio 12.4:1

The availability of parts for the 2008-2012 J-gen is much better than for the 87-07 F-gen. I think you will have a lot of difficulty finding aftermarket engine parts for the F gen. You may want to look for interchangability unless you want to have them built by a machinist. If you go the machinist route, I personally don't think the gains will be worth it. If you foresee spending any more than $4k you might as well get a 300, which has improvements across the board and higher potential gains from modifying the larger displacement engine.

Suspension work may get you from point A to point B a lot faster though, assuming there are curves in between.

[rabies]

ebay has pistons of 66mm n 13.1 cr ..hmmm
shops dont cost much. i jus had a gsr motor punched out from 81mm to 82mm with 12.1cr
cost about $140 with cleaning. then3pistonsxx. gaskets.bearings. no more then 800total if ur smart
small motorcycle block cofuldnt be more. assemble myself. its like a lego set. $3-4k? uh ..no
or jus do a ex500 swap

[Rollingmenace]

Thanks guys for all the comments ... I have seen that bike for sale .. As far as legality here in colorado their pretty easy to get along with here headlamp mirror and tail lamp is all that is required... I think that I'm gonna take several of his ideas and incorporate them into a build .. my brother works for a company that fabricates tanker trailers so i get all aluminum at scrap prices.. and one of his guys said he would tig the tank and body work for me... mmmm bare aluminuw all tigged up would look sweet...I'm starting with just a motor and a bare rolling frame and going from there I have a uline on a few nice pre gen rollers here... I guess it is what it is on these motors... Allthough I'd like more hp ill just deal as It will only be a ocassional cruiser .. I still can ride my girls 250 or my cbr 1000 if I want to get somewhere fast....