porting or not with RB mod's?

Questions and Answers about the best carb and Head mods available for the KDX.
Post Reply
commanderjjones
Member
Posts: 41
Joined: 09:08 pm May 15 2017
Country: United States

porting or not with RB mod's?

Post by commanderjjones »

I am doing a complete rebuild on my 220. Sent off the head, carb, and crank to RB. So while I have it torn down, I was considering sending the cylinder to Fredette for porting (evidently RB doesn't offer porting).

Any thoughts on this? I wanna get the best performance I can out of the bike without losing any bottom end power. And I really don't want a gas guzzler than I can't get 30 miles out of a tank.
cornishwrecker220
Member
Posts: 743
Joined: 06:37 am Nov 22 2009
Country:
Location: united kingdom

porting or not with RB mod's?

Post by cornishwrecker220 »

Would it not of been easier to have just sent your complete motor to Jeff & got him to rebuild it along with a port , head & carb mods ??

I have my 220 ported , a 36mm kx carb & head re-cut ...I asked for more power everywhere but I didn't want to loose my bottom end.... The end result is awesome, 40bhp measured on the dyno ( rear wheel ) I did have to fit a 10oz flywheel weight just to tame the hit ....it'll rip my mates 2015 ktm 200xc & I still get around 80 miles per tank grin:
commanderjjones
Member
Posts: 41
Joined: 09:08 pm May 15 2017
Country: United States

porting or not with RB mod's?

Post by commanderjjones »

cornishwrecker220 wrote:Would it not of been easier to have just sent your complete motor to Jeff & got him to rebuild it along with a port , head & carb mods ??
Looking back, yes it probably would have. But everyone on here spoke so highly of RB, I had already sort of made up my mind to go that way. Didn't think about the porting until I had already shipped the head, carb, and crank. Was really surprised to find out that RB didn't offer porting. WTH? :?
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: porting or not with RB mod's?

Post by KDXGarage »

He runs a machine shop, not a motorcycle shop??
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
jjavaman
Supporting Member II
Supporting Member II
Posts: 342
Joined: 11:20 pm Jul 23 2013
Country:

Re: porting or not with RB mod's?

Post by jjavaman »

Wait until you ride it before getting the porting done. I found with the head and carb mod the thing rips. I've beat every 250 4t I've raced. I'm seriously thinking of getting a flywheel weight to calm this thing down.
97-220 with a PC pipe. 2015- RB carb and head mod
User avatar
Tedh98
Supporting Member II
Supporting Member II
Posts: 1576
Joined: 01:08 pm Mar 20 2009
Country:
Location: Atlanta, Georgia
Contact:

Re: porting or not with RB mod's?

Post by Tedh98 »

Just cleanup the casting flaws and match the ports up and I think you will be happy.

port cleanup
commanderjjones
Member
Posts: 41
Joined: 09:08 pm May 15 2017
Country: United States

Re: porting or not with RB mod's?

Post by commanderjjones »

jjavaman wrote:Wait until you ride it before getting the porting done. I found with the head and carb mod the thing rips. I've beat every 250 4t I've raced. I'm seriously thinking of getting a flywheel weight to calm this thing down.
That's probably a good idea. Just thought about having it done while I'm waiting to get the other parts back. Having it down for 3 weeks really sucks........and I sold my spare bike last month. Gonna have to be a wuss and ride in the RZR for the next couple of weeks.
jjavaman
Supporting Member II
Supporting Member II
Posts: 342
Joined: 11:20 pm Jul 23 2013
Country:

Re: porting or not with RB mod's?

Post by jjavaman »

I've got a 73 RD350 in quite good shape and a complete numbers matching 74 parts bike! Love me my 2t motorcycles!
97-220 with a PC pipe. 2015- RB carb and head mod
User avatar
SS109
KDXRider.net
KDXRider.net
Posts: 5770
Joined: 05:11 am Aug 23 2009
Country: USA
Location: Tucson, AZ, USA
Contact:

Re: porting or not with RB mod's?

Post by SS109 »

Tedh98 wrote:Just cleanup the casting flaws and match the ports up and I think you will be happy.

port cleanup
Yup! That's what I did with my 220. The bike was good before but seemed to pick up some more top end after the rebuild and port clean up. I used small files to do the ports and I had it done in under 2 hours. Easy peasy!
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
commanderjjones
Member
Posts: 41
Joined: 09:08 pm May 15 2017
Country: United States

Re: porting or not with RB mod's?

Post by commanderjjones »

SS109 wrote:
Tedh98 wrote:Just cleanup the casting flaws and match the ports up and I think you will be happy.

port cleanup
Yup! That's what I did with my 220. The bike was good before but seemed to pick up some more top end after the rebuild and port clean up. I used small files to do the ports and I had it done in under 2 hours. Easy peasy!
Thanks, good to know!
Post Reply