Beginning a build, what would you do?

[Webber]

Alright guys, my R5 has been sitting in the shed with a bunk piston for two years now. I've been scouring the internet but want your thoughts. What's the best combo you guys have seen to get some serious horsepower down. Bike won't be on the track but won't go on rides longer than 30-60km at a time, not overly worried about expenses or longevity where it gets in the way of power substantially.

I'm seeing these mods online but having a hard time seeing the obvious winners:

Current status:

-4000km, bored 2 sizes over.
-Oil pump currently installed and working but will likely be removed.
-Barret clutch springs and plates but still having slip issues.
-Hole size of a dime in the center of right piston. I'm assuming pre-ignition issues.
-Stock point system.
-Stock mikuni
-K&N Y Boot

What would your dream build incorporate?

(Engines getting fully stripped down to do all the seals and leak down.)

-RD 350 or 400 jugs and heads with RV's?
-LC conversion?
-Mill out to accept bigger cages?
-Bigger carb or Lectron/smart carb?
-Ignition is a must, who's the clear winner these days?
-Long Stroke bottom end?
-Nikasil the Jugs?
-Expansion Chambers?
-Clutch, what damn clutch to never slip again.
-Etc, etc, let me know what you guys would do.

[85RZwade]

[m in sc]

i mean, if you want to lc it, new cyls are available from webike and will bolt right on. 

on my 72R5 I put on a set of the cheap reproduction aircooled cyls and have actually been VERY happy with them (and i already have an lc converted bike).

get a vape cdi and a programmable igniton as well, highly recommend, and a good disc brake setup after the HP is added.

[Webber]

i mean, if you want to lc it, new cyls are available from webike and will bolt right on. 

on my 72R5 I put on a set of the cheap reproduction aircooled cyls and have actually been VERY happy with them (and i already have an lc converted bike).

get a vape cdi and a programmable igniton as well, highly recommend, and a good disc brake setup after the HP is added.

Vape CDI, okay thanks I'll check er out! I'm not seeing the jugs on Webike? Got a link for my dumbass?
I suppose if I'm looking to jack this thing up LC is a not essential but realistic for sure

[m in sc]

it says RZ, but these are non powervalve LC cyls. 

[Webber]

it says RZ, but these are non powervalve LC cyls. 

You mean to tell me I can drop these on the r5 case!?

https://japan.webike.net/products/25625106.html#specification

[rodneya]

https://www.jl-exhausts.com/tz-engine-parts-559-c.asp

Or a replica TZ topend

[m in sc]

yes. bolts right on. will need to mount a radiator obviously and a water pump, also some longer cyl studs which yambits sells. I've done this a few times as have others. note, the exhaust flange is wider. and YES, you 'can' run stock RD/R5 pipes if you choose but need to lengthen the headpipe at the muffler about 1" (yes, ive actually done this)

[teazer]

So many choices. 
Long stroke: No
Water cooled: OK but not a lot of advantages over air cooled but if you need an RD top end, it's worth thinking about.  TZ top end is a lot of $$$ and pistons are hard to get and expensive
Air Cooled: Yes.  Fit an RD top end and have it ported
Chambers: Absolutely.  JL are beautiful, Spec2 are awesome, other choices as well
Reeds: YZ85 reed cages and open up the reed boxes to fit them with spacers
Long Rods: sure but not necessary for a street bike
Carbs: bore to 29.5mm or buy flatslides
Ignition: Vape, ignitech, Zeeltronic, HPI.  Vape is probably the best option.
Brakes: Upgraded disk rotor and caliper for sure.  Probably blue dots on an adapter
Suspension: Race tech or mike's XS gold valve emulators at least, or complete FZR400 front end with matched shocks at the rear.
Heads: minimum get squish corrected, or Vintage Performance or other aftermarket heads

[m in sc]

I mean it depends what your overall goals are. there's plenty of ways to skin a cat. if you want simple def go aircooled.  I disagree there's no advantage to lc, the porting is better out of the box and keeping temps under control is obviously much easier. but its expensive

[Webber]

Thanks a ton for all the input, went down the cpi big bore rabbit hole, TZ, etc. As it stand I'm leaning towards this:

Cylinders: Webike LC jugs (Nikasil is nice to see)
LC set up TBD

Exhaust: Tyga or JL

Clutch: TBD

Carbs: Still mulling over the idea of smart or lectron even knowing the potential top end loss and ridiculous price. Dug into 2-1 like the banshees run. Pretty hard to find upsides with that set up haha.

Ignition: Vape with Zeel

[Webber]

Once I move the bike to somewhere suitable to pull wrenches I'll be rebuilding the spare r5 that I got with it. Hoping to restore it and sell it to partially finance this build. Should have enough parts to restore the part bike thankfully.

[rodneya]

Thanks a ton for all the input, went down the cpi big bore rabbit hole, TZ, etc. As it stand I'm leaning towards this:

Cylinders: Webike LC jugs (Nikasil is nice to see)
LC set up TBD

Exhaust: Tyga or JL

Clutch: TBD

Carbs: Still mulling over the idea of smart or lectron even knowing the potential top end loss and ridiculous price. Dug into 2-1 like the banshees run. Pretty hard to find upsides with that set up haha.

Ignition: Vape with Zeel

The Tyga pipes look sweet. Much better than the JL in my opinion. The stuff I have bought from Tyga is top quality.

[m in sc]

a solid set of TM32/34/36 will work just fine for HP. heck, i know you can pull 70 HP thru a set of 30s.

no need to go lectron or smart carb. that's just a waste of money IMHO unless you are going drag racing.

[teazer]

I have to agree with Mark. An RZ easily makes 60hp with teeny tiny 26mm carbs.  30 - 34 are nice but depends on how you ride and what you are looking for.