XR650L Jetting help Full modded Big Bore XR 680 L.

[craig hammon]

Motor mods.

Smog block off.

FCR  MX. 41 mm. Kehin flat slide pumper carb

XRsOnly big fin head ported with big valves

FMF Power Bomb Header

Air box moded

10.5-1 piston

D.G. slip on

Stage 2 hot cam.

I had it running well with the stock cam with a 48 P and a 180 Main jet.

because my mechanic istalled something wrong the auto decompress didn't work so I had him switch out the cams. 

When I got it back it seemed to run rich it lost some low end torque, so I installed a 172 main and a 45 P.

It ran better with the stock cam?

Sea level.

Edited August 20, 2019 by craig hammon

[notoriousE-R-I-C]

You are (sea level); Rich on main and

Lean on pilot

45pilot

155main

Is my suggestion.

And use 91 or higher. That CR needs higher octane. Specially now the Hotcam. No decomp.

 

 

[craig hammon]

6 minutes ago, notoriousE-R-I-C said:

You are (sea level); Rich on main and

Lean on pilot

45pilot

155main

Is my suggestion.

And use 91 or higher. That CR needs higher octane. Specially now the Hotcam. No decomp.

 

 

OOOPs it had a 48 and now a 45P so a 155 main from a 172. wow.

With the stock cam it would ping on 91 till I installed the 180 main.

 

[notoriousE-R-I-C]

Your pinging needs you to go up on fuel quality. Go buy some race gas...maybe not use 100% of it...but cut the 91 with it.

Not fuel amount in A/F Ratio

45 was perfect for me on a stock bore and perfect for a bored up comped up rebuild.

The cam...maybe could call for the 48.

(Next to what IN and EX you have)

But my bored up bike has a cam in it too. The stock bore build has a stock cam.

They're both 45

The differences in jetting was how much intake flow and how much exhaust flow they had.

I ran both motors with both exhausts and intakes.

I also want to say I am 155 with stock airbox and oiled Uni filter. Remove that airbox and manifold off the carb, put an oiled Uni pod filter on it...I needed to up the main to 160.

160 no airbox and a Powercore4 with xl600 headers.

So 180 sounds thick.

 

 

[baldy110]

Where'd you get a stage 2 cam?

[EarthCruzn]

Stage 1,2,3 & 4 if ya need it.,,,,,,,.I guess they make what you put in it.

But I hear the cam in the stock XR650L is actually pretty good, ...... 

 

VALVE LIFT DURATION DURATION @ .050 GRIND NUMBER DESCRIPTION


Honda XR 650 L RFVC SOHC 4v
265°/265°295°/295°.380/.370 240/239 Special racing cam.  Requires Exhaust System, High Compression Piston, Shortened Valve Guides, and Performance Valve Spring Kit. Check
$286.00
256°/248°280°/274°.380/.365 213/202 Performance profile designed to increase mid and upper end. Requires Exhaust System, High Compression Piston, Shortened Valve Guides, and Performance Valve Spring Kit.
$286.00
256°/256°280°/280°.370/.350 450/451 All around performance with added mid and upper end performance. Requires Exhaust System, High Compression Piston, and Performance Valve Spring Kit.
$286.00
242°/242°267°/267°.355/.355 235/236 Bolt in profile increases overall performance throughout RPM range. Excellent torque. $286.00

[baldy110]

He's using a stage 2 HOT CAM. I'd like to know where he bought it.

[EarthCruzn]

3 hours ago, baldy110 said:

He's using a stage 2 HOT CAM. I'd like to know where he bought it.

Maybe here

http://www.hotcamsinc.com/Default.aspx

 

 

[baldy110]

According to their website a stage 2 is not available for the XR. So again where did he get a stage 2 from Hot Cam?

[craig hammon]

The shop that built my motor got most of the parts from XR's Only. I am now running a 158 main and a 45 pilot and its too lean. Almost ready for a Baja surf trip this weekend. I am going to install the 48 pilot jet.

Edited August 22, 2019 by craig hammon

[craig hammon]

On 8/20/2019 at 4:27 PM, EarthCruzn said:

Stage 1,2,3 & 4 if ya need it.,,,,,,,.I guess they make what you put in it.

But I hear the cam in the stock XR650L is actually pretty good, ...... 

 

VALVE LIFT DURATION DURATION @ .050 GRIND NUMBER DESCRIPTION


Honda XR 650 L RFVC SOHC 4v
265°/265°295°/295°.380/.370 240/239 Special racing cam.  Requires Exhaust System, High Compression Piston, Shortened Valve Guides, and Performance Valve Spring Kit. Check
$286.00
256°/248°280°/274°.380/.365 213/202 Performance profile designed to increase mid and upper end. Requires Exhaust System, High Compression Piston, Shortened Valve Guides, and Performance Valve Spring Kit.
$286.00
256°/256°280°/280°.370/.350 450/451 All around performance with added mid and upper end performance. Requires Exhaust System, High Compression Piston, and Performance Valve Spring Kit.
$286.00
242°/242°267°/267°.355/.355 235/236 Bolt in profile increases overall performance throughout RPM range. Excellent torque. $286.00

My bike had higher compression with the stock cam. but  it pinnged. 

[timbanditos]

Considered dropping the needle one clip? Sometimes that can lean everything out just a little.

The shop that built my motor got most of the parts from XR's Only. I am now running a 158 main and a 45 pilot and its too lean. Almost ready for a Baja surf trip this weekend. I am going to install the 48 pilot jet.

[beezer]

My bike is very similar to the OP's but with a Web Cam.

The pinging was solved with a programmable Ignitech CDI box.

Bike ran much better.

[Oregon lightweight moto]

Motor mods.
Smog block off.
FCR  MX. 41 mm. Kehin flat slide pumper carb
XRsOnly big fin head ported with big valves
FMF Power Bomb Header
Air box moded
10.5-1 piston
D.G. slip on
Stage 2 hot cam.
I had it running well with the stock cam with a 48 P and a 180 Main jet.
because my mechanic istalled something wrong the auto decompress didn't work so I had him switch out the cams. 
When I got it back it seemed to run rich it lost some low end torque, so I installed a 172 main and a 45 P.
It ran better with the stock cam[emoji37]
Sea level.

Most people like the stock cam better. It’s solely focused on low to mid power, which is where a vast majority of riders stay in the powerband. The pig just wasn’t designed to scream like modern bikes. I just ordered the carb you
Have so I look forward to tinkering with it on the pig.

[EarthCruzn]

On ‎8‎/‎21‎/‎2019 at 11:48 PM, craig hammon said:

The shop that built my motor got most of the parts from XR's Only. I am now running a 158 main and a 45 pilot and its too lean. Almost ready for a Baja surf trip this weekend. I am going to install the 48 pilot jet.

Why do you say it is too lean?

[craig hammon]

8 hours ago, EarthCruzn said:

Why do you say it is too lean?

It gets tooo hot.

[EarthCruzn]

13 hours ago, craig hammon said:

It gets tooo hot.

I would personally go with the stock cam.....................

you will have power from the upgrades already done................. the stock cam is actually a very good medium in the power dept.

the cam maybe the cause of the issues you are having..................

remember making improvements in "power performance" can take away "engine performance".

a good running well temperature maintaining engine is usually NOT very modified.

[mg600]

What needle are you using