ADVrider

Go Back   ADVrider > Bikes > Thumpers
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 12-21-2011, 03:17 PM   #16
sc-razor
Beastly Adventurer
 
sc-razor's Avatar
 
Joined: May 2008
Location: NW Arkansas
Oddometer: 3,746
I knew Wattner would be first
__________________
2009 XR650L

Steve
sc-razor is offline   Reply With Quote
Old 12-22-2011, 01:12 PM   #17
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Just posted in another thread on thumper talk, asking about FCR carbs and tank clearance. Want to run FCR's on these bikes, the newer-style FCR (not the slant-body), but what size? What's the consensus? Two of the bikes are pretty much stock, and one of them is fully-built (cam, big-bore kit, ported big-fin head, full exhaust, etc.). Used a Noss adapter when I put an FCR on my 650R and was really happy with it. So figured I'd order a few more for these bikes. They do make them for this application, right?
jesusgatos is offline   Reply With Quote
Old 12-22-2011, 01:17 PM   #18
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
paging cyclewizard...
jesusgatos is offline   Reply With Quote
Old 12-22-2011, 01:38 PM   #19
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Little bit of research dug up some good info on this subject (adapting FCR carb to XR650L).

This post by Research Rat on TT regarding different sizes:

Quote:
Originally Posted by Research Rat View Post
I spoke with Sudco today re 39, 40, 41.

1. All fcr mx models have the same dimensions. IE no fuel volume capability difference.
2. 39, 40, 41 is the size of the internal venturi opening.
3. When Sudco dynoed different carbs on an xr650l, there are smallhp difference between 39, 40, or 41 mm sized models. "Negligable differences" was the term used.
4. The 39 will produce better down low reponse than 41, 41 will conversely produce better high end response than 39.
5. The Sudco contact remarked that he'd seen good results with using the 39 mm on xr650ls.

The Sudco contact recommended thinking less about engine size in relation to venturi size needed, rather than relationship between hp and venturi size. His rationale, crf450r with a 40 venturi opening, makes more HP than xr650l with the 41 venturi opening. I still don't understand this as 450 has 200 less cc's than the xrl and consequently would require a smaller overall combusatable mix.

All the above aside, our bikes need a measured amount of fuel/air, which is based on engine size. I think the 39 mm with rejetting can deliver the "right amount" but the question is can it deliver at the same rate of speed as what's needed. I'm not sure about that yet.

Thoughts?
-Scott

And a long thread about jetting that I haven't had time to read yet.
jesusgatos is offline   Reply With Quote
Old 12-22-2011, 02:39 PM   #20
cyclewizard
Beastly Adventurer
 
cyclewizard's Avatar
 
Joined: May 2007
Location: Norway/Michigan.
Oddometer: 4,797
Quote:
Originally Posted by jesusgatos View Post
paging cyclewizard...
Yep Sudco makes a nos adapter for the FCR41 but it's to short in my book for a good fit on the air box side but will work with a little muscle.. they should have made it longer like I'm going to do...
I'm working on some aluminum billet intakes that can be ported to match the head porting at the monent.
I like the idea of the billet intakes over the hard rubber ones, once you grind out the rubber ones to fit the race ported heads there's not much material left over. Besides that the aluminum won't crack and smoke your new motor that you just spent a grand or so on.
Also the aluminum intake has a straighter shot going from the carb to the head and valves which will give you more POWER...
The big bend on the oem intake hurts performance.

I like the FCR45's over the 41's, it seems like the 41's run out of moe-joe in the upper revs and taller gears on the big block motors..for a 1mm or 2mm over high comp motor they work fine and I think they're the best carb out, almost like EFI they're so darn good.

This is no lie once you pump up a XRL with a cam some head porting and some comp the CV carb performs quite well..when you pump one up to a big block motor they do even better....
__________________
C-dub......


Powered by CW-Pistons/cams
Wizard manufacturing....
cyclewizard is offline   Reply With Quote
Old 12-22-2011, 02:51 PM   #21
cyclewizard
Beastly Adventurer
 
cyclewizard's Avatar
 
Joined: May 2007
Location: Norway/Michigan.
Oddometer: 4,797
Love that tank......cool thread how did I miss it?
The man has some skills..
__________________
C-dub......


Powered by CW-Pistons/cams
Wizard manufacturing....
cyclewizard is offline   Reply With Quote
Old 12-22-2011, 03:57 PM   #22
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Quoting cycle wizard's reply to a PM I sent him about this for everyone else's' benefit:
Quote:
Originally Posted by cyclewizard
There's no clearance issues with the FCR or 42 micky..
The fcr is a bit easier to take on and off than the micky but the micky is easier to ajust the pump and jet.
Quote:
Originally Posted by cyclewizard View Post
Yep Sudco makes a nos adapter for the FCR41 but it's to short in my book for a good fit on the air box side but will work with a little muscle.. they should have made it longer like I'm going to do...
I'm working on some aluminum billet intakes that can be ported to match the head porting at the monent.
I like the idea of the billet intakes over the hard rubber ones, once you grind out the rubber ones to fit the race ported heads there's not much material left over. Besides that the aluminum won't crack and smoke your new motor that you just spent a grand or so on.
Also the aluminum intake has a straighter shot going from the carb to the head and valves which will give you more POWER...
The big bend on the oem intake hurts performance.

I like the FCR45's over the 41's, it seems like the 41's run out of moe-joe in the upper revs and taller gears on the big block motors..for a 1mm or 2mm over high comp motor they work fine and I think they're the best carb out, almost like EFI they're so darn good.

This is no lie once you pump up a XRL with a cam some head porting and some comp the CV carb performs quite well..when you pump one up to a big block motor they do even better....
45's huh!?! wow. Would like to know more about these intakes that you're working on. Any idea when I might be able to get my hands on a few of those? And Lemme know if you need any help with CAD modeling or whatever. Oh, and would we still need to use a Noss adapter on the other side of using the stock air-boot?
jesusgatos is offline   Reply With Quote
Old 12-23-2011, 05:48 AM   #23
cyclewizard
Beastly Adventurer
 
cyclewizard's Avatar
 
Joined: May 2007
Location: Norway/Michigan.
Oddometer: 4,797
Quote:
Originally Posted by jesusgatos View Post
Quoting cycle wizard's reply to a PM I sent him about this for everyone else's' benefit:



45's huh!?! wow. Would like to know more about these intakes that you're working on. Any idea when I might be able to get my hands on a few of those? And Lemme know if you need any help with CAD modeling or whatever. Oh, and would we still need to use a Noss adapter on the other side of using the stock air-boot?
Yep you would still need the air box adapter but the new intake is going to be longer so it fits the air boot better.
I'll post a pic of a billet intake that I'm building for a national flat tracker, he's running one of my 750 motors..
It's a Knight frame twin shock so I'm making a straight intake for it that will fit his 48mm carb..
__________________
C-dub......


Powered by CW-Pistons/cams
Wizard manufacturing....
cyclewizard is offline   Reply With Quote
Old 12-23-2011, 05:56 AM   #24
cyclewizard
Beastly Adventurer
 
cyclewizard's Avatar
 
Joined: May 2007
Location: Norway/Michigan.
Oddometer: 4,797
To bad you couldn't relocate the rear shock I could build you a cross flow twin carb billet intake.
Two 32mm carbs with pod filters..
__________________
C-dub......


Powered by CW-Pistons/cams
Wizard manufacturing....
cyclewizard is offline   Reply With Quote
Old 01-03-2012, 03:13 PM   #25
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Please do post some pics. Would love to see what you're working on.
jesusgatos is offline   Reply With Quote
Old 01-03-2012, 03:22 PM   #26
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Made some more progress on the tank, and took a bunch of pictures with a new camera that I just bought, but I can't figure out where I put the damn things. So here are a few crappy cellphone pics instead. Started re-shaping the underside of the tank, and what these don't document too well is how I fit and shaped and cut the sheetmetal, tack-welded it into position, installed temporary supports, taped-off the interior volume, filled it with expanding foam, and then cut away the excess. The whole point of this was to, 1) maximize volume, and 2) make the tank a bit easier to reproduce.







jesusgatos is offline   Reply With Quote
Old 01-03-2012, 03:24 PM   #27
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Also spent a bit more time re-shaping the topside of the tank and it's looking a lot better. Funny how a few small changes can all add up to make such a big difference in the overall look and feel of something. Or maybe I've just spent too much time fondling this tank...
jesusgatos is offline   Reply With Quote
Old 01-03-2012, 04:11 PM   #28
VxZeroKnots
Beastly Adventurer
 
VxZeroKnots's Avatar
 
Joined: Jun 2008
Location: Durango CO
Oddometer: 2,557
Keep it coming Jesse!
__________________
I say we take off and nuke the entire site from orbit. It's the only way to be sure

No bike does everything perfectly. In fact, no bike does anything until someone gets on it to ride.

VxZeroKnots is offline   Reply With Quote
Old 01-04-2012, 09:03 PM   #29
XRider
Almost Lifelike
 
XRider's Avatar
 
Joined: Oct 2006
Location: Los Gatos, CA
Oddometer: 1,255
Very nice!
__________________
XR650R Plated Supermoto
XR628R Plated and highly modified
CR500R Still rips after all these beers
RZ350L Kenny Roberts Special
BMW 1150GS It's like ridding a Barkalounger
XRider is offline   Reply With Quote
Old 02-11-2012, 08:38 PM   #30
jesusgatos OP
fishing with dynamite
 
jesusgatos's Avatar
 
Joined: Nov 2006
Location: on the road
Oddometer: 2,342
Haven't had much time to work on this project lately, but spent this afternoon mocking-up the new subframe. It's pretty wonky, but just wanted to throw something together quick-like. Gonna make some small adjustments after I fit the rear fender, then make make a jig and I can weld-up the real subframes.



jesusgatos is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 01:51 PM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014