RX-3 down....

[SpudRider]

Thanks for posting the update.

[rtking]

Thanks for sharing, Superdude! That is a handsome polish job on the intake! Can't wait to hear how the bike responds to the ported and polished head.

[Weldangrind]

Will the exhaust side be polished as well?

[superdude]

Originally Posted by Weldangrind

Will the exhaust side be polished as well?

Not sure. Is that standard for both intake and exhaust sides to be polished? Its already put back together Gerry took it out for a test ride with the new motor and p/p job and said its real nice. Now on its way back up here via expedited/direct car shipper should be here in a couple days, which makes exactly 3 weeks from the time it crapped out until its back in my buddys garage. Not too shabby considering spent a few days just to diagnose and then shipping back and forth. I've seen a little bit on the blog about someone who ported and polished their 250 in one of the replica mustang bikes. Does anyone have anyone have a rough idea on what the HP increase is on a thumper thats ported and polished? 3-5 horsepower? I know for cars you can see gains of 5% but I have no clue if that applies to a single cylinder motorcycle as well.

[detours]

A 5% gain on 25 HP isn't a lot. On the other hand, every bit counts and if it adds even a little more torque, you'll feel it. But I would expect demonstrable gains in throttle response, and that would be nice.

What do they charge for the port and polish?

[SpudRider]

Perhaps my memory fails me, but I think the price for a port and polish is $800. I think we will get a better performance increase from an EJK fuel controller, which only costs $250. If you guys are interested in the EJK controller, please send an email to sales@dobekperformance.com.

http://www.chinariders.net/showthread.php?t=15565

[superdude]

Heres Gerrys response regarding break in procedure..might be worth adding to the maintenance and mod sticky under "break in" since doesnt get any better than from the horses mouth and pertains solely to the RX-3:

"
Shipped out your bike today
As far as break in
You should not rev the engine beyond 7 k rpm for the first 500 miles
What I mean is that no sustained rpm above 7 k
A good break in has varied rpm and throttle angles/loads. Avoid sustained rpms and over heating

I already did a oil change on the new motor after I put 50 miles on it
So don’t replace engine oil until 600 miles ( use synthetic oil 10/40w)
Also at that time you need to check / adjust valve lash .003” both in and out valves

When engines suffer damage like yours did its always due to over rev / heating during the break in period. Its easy to do because its only a 250cc. so becareful to allow for break in.

Some other advise-
When starting : turn key on and push start button ( nothing else ) allow to warm up atleast 1 bar.
Do not blip throttle during deceleration. Doing so can cause additional back fire since the computer thinks you want more fuel
Install lucas top end cyl lubricant / fuel conditioner in the fuel tank at least for the first 600 miles. I use it all the time since our fuels are lacking in lubricant. It helps keep things working properly and the engine loves it.

Don’t forget you need to check nuts and bolts for tightness at all service intervals

Also, to take full advantage of the head work you should consider power commander or similar piggy back fuel manager. A performance muffler / slip on as well. I prefer supertrapp slip on.

Enjoy the bike

Thank you

CSC service manager
Gerry Edwards"

[superdude]

Originally Posted by SpudRider

Perhaps my memory fails me, but I think the price for a port and polish is $800. I think we will get a better performance increase from an EJK fuel controller, which only costs $250. If you guys are interested in the EJK controller, please send an email to sales@dobekperformance.com.

http://www.chinariders.net/showthread.php?t=15565

FYI Spud I tried the email address for dobek you provided and sent them an email right after you posted that and both times it got sent back to me as invalid email address.

[SpudRider]

Originally Posted by superdude

FYI Spud I tried the email address for dobek you provided and sent them an email right after you posted that and both times it got sent back to me as invalid email address.

Thanks for letting me know about the bad email address. I will call Dobeck Performance, and get a good email address from them.

[Weldangrind]

Originally Posted by superdude

Is that standard for both intake and exhaust sides to be polished?

Not necessarily. That said, a mirror polish is only a benefit on the exhaust side, whereas the intake side needs a little texture to promote atomization. The polishing on an intake can be like a mirror, if the injector is downstream of the intake (i.e. a dry-flow system).

It's important to not remove too much material when porting on the intake side. Knife edge the plenum wall, remove rough casting, blend any short radius, lightly polish and call it a win.

[Weldangrind]

Originally Posted by superdude

Do not blip throttle during deceleration. Doing so can cause additional back fire since the computer thinks you want more fuel.

Two things come to mind here.

1. I always blip the throttle on deceleration, to remove excess load as I downshift.
2. Backfire is the result of a lean mixture, not excess fuel. Perhaps blipping the throttle adds more air very quickly, before the injector can respond.

I don't actually have any formal training. I'm just a goofball who reads too much.

[superdude]

Update: Bike arrived on friday back to my buddies house. they swapped out the sprockets for him as well to the 13t, and he has the brand spankin new motor with the port and polish on it. After he got it, he rode it to work and wanted to really break it in so he rode at 84 mph for 50 miles WOT and so far no issue. ha just kidding. he did ride it to work though which should be perfect break in rides commuting downtown seattle lots of variation. CSC also took care of a paint chip he had on his tank. He said the motor feels almost exactly like the one he sent back, which is a good thing since old one was semi broken in and this new one with p/p is not. I'll post more updates on the upgraded head especially when we ride our bikes together and both are broken in and can compare apples to apples. We're also taking our rx3's to a dyno and EFI tuner sometime next couple months the owner said he really wants to have an rx3 to test in his shop so that'll be fun to see what he can squeeze out of them and what the numbers are on my buddies bike.

All in all pretty tough to beat CSC's service especially Gerry for taking care of everything they said they would do. Essentially its not 100% their fault yet they went above and beyond, and that is a great way to do business and very comforting for all other RX-3/CSC bike owners.

[SpudRider]

Thanks for posting the update. CSC provides unparalleled customer service.

[DanKearney]

Your buddy was told by CSC:

"As far as break in You should not rev the engine beyond 7 k rpm for the first 500 miles
What I mean is that no sustained rpm above 7 k"

and then he:

"After he got it, he rode it to work and wanted to really break it in so he rode at 84 mph for 50 miles WOT and so far no issue."

Wow. I think he's asking for more trouble.

Cheers,

Dan K.

[Danimal]

Originally Posted by DanKearney

Your buddy was told by CSC:

"As far as break in You should not rev the engine beyond 7 k rpm for the first 500 miles
What I mean is that no sustained rpm above 7 k"

and then he:

"After he got it, he rode it to work and wanted to really break it in so he rode at 84 mph for 50 miles WOT and so far no issue."

Wow. I think he's asking for more trouble.

Cheers,

Dan K.

He followed that statement with j/k