Messages

1

Vintage Two Strokes / RM500 Refresh

« on: August 11, 2014, 10:44:41 PM »

Sweet ride!  Should be a hoot to ride/race.

You don't see many open class Suzukis these days, so the
cool factor is over on the "way cool" side of the scale.

dogger

2

Vintage Two Strokes / Pro-circuit pipes?

« on: April 13, 2014, 05:57:35 PM »

where to drill the holes in the crankcase to ease oil flow to the clutch?

I just sent someone some pictures on that on another site.  If that wasn't you, let me
know and I'll send them to you as well.

dogger

3

Vintage Two Strokes / Pro-circuit pipes?

« on: April 06, 2014, 06:08:36 PM »

the slide is a 1360?

I'm hoping that number is a 1369, if so, you should be good to go for a baseline.
If it really is a 1360, you'll need to swap it out.  The needle will affect performance
from 1/4 throttle all the way to where the main jet takes over.

From the pictures, looks like a nice ride.

dogger

4

Vintage Two Strokes / Pro-circuit pipes?

« on: April 05, 2014, 03:50:46 PM »

doesnt run too well with 195 main jet it just drowns in goo

Wow! no wonder.  Where did you come up with a 195 main?

Here is a good baseline jetting start using the PWK.  Tweak it from here for your temps and
altitudes: 168 main, 55 pilot, 1370M needle with clip on 3nd and the airscrew 1 1/2 turns out.

dogger

5

General Two Stroke Talk / 500 thoughts

« on: June 17, 2013, 05:05:00 AM »

what is the better motor and the pros and cons over each other?

Both are great motors.  Your choice should depend on intended use, parts availability
and to a lesser extent, brand loyalty.

I did a lot of research before starting a similar project a couple of years ago.  The
advantage I had is I raced 500s before the class went away.  I knew what I was
getting into and I knew what modifications were needed to be able to survive a
moto.

To be honest, I didn't even consider the KX as I consider it more of a desert racer
than a MX motor.  The CR is also easy to get parts for and there is a ton of support
available due to the popularity of the numerous CR based  "AF" conversions out there.

With that said, In stock trim, the late model CR is not a good MX engine.  It comes with
a wide ratio transmission and has a substantial hit that will stretch your arms and wear
you out in short order.  It also vibrates pretty good.  The one thing you don't want is a
mid 80s CR500 engine.  Those engines were so powerful that even the factory riders had
them detuned.  Throw in the corrosion problems from Mag water pump covers and the very
long list of NLA parts and you'll have a big mess on your hands.

Here is a partial list of the modifications I performed to correct a 2000 CR 500 shortcomings:

Close ratio tranny
Balanced and trued crank
Aluminum cylinder sleeve
Digital 3D ignition
Port and head work to lessen the hit
Aftermarket pipe and silencer
Aftermarket clutch

I opted for a 2008 Honda CRF250R frame over any of the newer models.  The frame geometry
on the 06-09 CRF250 is very similar to the 93 CR250, which is one of my favorites.  I also like
the slimmed down size and lighter weight over the 450F.  I'm 6'1" and that frame fits me
perfectly. 

What I have now is 60+ of more useable horsepower in a lightweight, modern chassis with state
of the art suspension.  The bike is deceptively fast because you don't have to wring it out to make
power.  All you have is the wind noise in your helmet and the corner approaching way quicker than
you expect - the first mods I made after I finished the bike was a pair of oversized wave rotors.  If
I had this bike back in the 90s, I would have won a lot more races.   

If you are a Kawasaki fan, some of the same mods would apply as well.  Like I said, both are great
engines and both will make an awesome MXer in the right roller.

I would say you have a lot of research to do and some big decisions to make.

My two cents.

Good luck.

dogger

6

Vintage Two Strokes / RM250 Rebuild

« on: June 01, 2013, 05:45:47 PM »

Wow! This is a really nice build!

Some nice improvising on the pegs and clutch basket.

The wheels and frame turned out great, can't wait to see
the next installment.

dogger

7

Technical / CR 250 primary drive gear collar seal size ?

« on: May 29, 2013, 05:37:16 PM »

Have come to the primary drive collar and the seal inside it thats missing. Clymer says to replace but honda parts drawings dont show the seal. Has anyone come across this and know what size seal to replace it with.

OK, the reason the Honda fiche doesn't show an Oring is because there isn't one.  There are two such collars on a CR250, one at the primary and one at the shift lever.  Because of the design, only the shift lever collar gets an Oring.
Grease up the lip of the seal and another layer of grease on the collar before install and you're good to go.

dogger 

8

General Two Stroke Talk / Trustworthy Piston and Con-rod Brands??

« on: April 18, 2013, 05:31:51 PM »

im looking to get a definitive list

Good luck with that one.  As you can see from the responses, as far as most people are concerned,
pretty much every brand available is considered "safe".

What I recommend, depends on the bike.  Some brands of OE are better than anything aftermarket. 
Others, not so much.  It also depends on how the engine will be used and how often it will be torn
down for maintenance.  Most brands and OEs are "safe" to a certain extent.  Since you didn't list
any particulars about your bike (size, brand, use etc.), it's hard to offer opinions of what will work
best, or be "safe" as you requested

dogger

9

Technical / CR250R Keihin PWK/mikuni carb swap questions

« on: April 14, 2013, 04:30:27 PM »

Are there any tricks to disconnecting the TPS?

If you think you might sell the bike someday and decide to keep the TMX so
that it can be re-installed, leave the wire in place.  I like to fold the wire on
itself then cover the whole thing with some heat shrink tubing to protect
the terminal.  Use a zip tie to secure the bundled wire.  Electrical tape will
work fine, just keep an eye on it.

If you know you won't ever use the wire again, cut it short and cover the end
with a  terminal end heat shrink boot to keep the elements out.

dogger

10

Technical / CR250R Keihin PWK/mikuni carb swap questions

« on: April 13, 2013, 10:54:55 PM »

Yes, the TMX is a short body and this version of the PWK a long body, but this is a common swap and the boot can be fitted with a
bit of wrestling.  If you want a easier fit, you can swap your current boot with a 2000 CR250 model and it will be the right length
since that bike came with the same PWK.  Air boots are cheap and readily available from Honda.

dogger

11

Vintage Two Strokes / My 1979 cr250

« on: April 13, 2013, 06:25:37 PM »

I'm talking about the intake between the cylinder and carb

That part is available from Honda for $63.
http://www.partzilla.com/parts/detail/honda/HP-16221-430-000.html

dogger

12

Vintage Two Strokes / My 1979 cr250

« on: April 12, 2013, 05:12:33 PM »

Does anyone have a 78-80 cr250 intake?

When you say intake, I'm assuming you mean the airboot between the filter
and carb.  If that's the case, and you plan to ride/race the bike, a lot of people
use the Twin Air integrated filter.  It comes with the rubber boot bonded to the
filter.  I use one whenever I run my 79 so I don't have to fool with the hard to
service OE filter.  The filter tube threads in through the hole in the airbox
directly to the carb.

dogger

13

Technical / qustion 2001 cr250

« on: March 31, 2013, 03:49:59 PM »

i was riding then out of a sudden my back tire locked up...i just dont wanna spend 900 + on this bike and i ride a 2001 cr250

Save your money.  Sell the 01, You could probably get a decent price for it even with a blown engine
because it's a sought after model. 

If you still want to ride something, check out an XR or CRF.

dogger

14

Vintage Two Strokes / 1978 C2 RM250 Project

« on: March 27, 2013, 01:09:43 AM »

First, I would send that crankshaft to Racers Toy Store or some other shop that deals in vintage cranks to have the
crank rebuilt with a new big end bearing.  While it's apart, they can clean the halves and media blast the rod and
resize both ends.  I don't know what else you have that is rusted, but WD40 Rust soak works great on steel parts. 
Just put everything in and soak over night. 

You can do a lot better than DC plastic.  Try this site:  http://vintage-suzuki.com/en/
They carry a fair amount of items for your project.

The ultrasonic parts washer will be useless for 90% of what you're doing at this stage.  Once you get the steel parts
rust free, the Aluminum parts media blasted, all the paint and other crap off, you can start thinking about using it. 
You will need to acquire metal  specific cleaners to use in that kind of washer.  It is great at cleaning carb bodies,
removing media and grit from freshly honed cylinders, etc.

If I were you, i would concentrate all of my efforts on getting that basket case engine running again.  If you start
going in all different direction with shocks, plastic and other minutia, this project will get out of control in a hurry.

dogger

15

Technical / Cr 250 2003 barrel relining

« on: March 27, 2013, 12:41:16 AM »

how much it costs to get a cr250 2003 barrel relined

Not sure what you are asking.  If you want to resleeve your cylinder, it will cost
around $200 for the sleeve and another $225 to have it plated.  If by "relined"
you are talking about replated, that will cost you $225 at Millennnium
Technologies.  For a resleeve and replate, you're better off getting a new
cylinder.

dogger