Upgrade piston, camshaft and carburator for XR650L

[mcma111]

Your correct with the 102.4mm piston with the OE sleeve.

[RichNX650boy]

To Nic from Manchester / Roma .
Hello to everyone I have just joined this excellent forum in London.
Very interesting reading here all the various engine mods available .Love the 105mm piston, XR carb,idea.
Nic First question.Where did you get your XR650L from? I was not aware that they were available in England.
Did you have it imported from the States?
2. Re:NX650 Dominator gear ratio modifications .I had a 1997 NX650 from new and sold it with only 8000 miles on it. I hated the overdrive 5th gear with the big gap down to 4th but maybe it works out on your XR650L bikes. .
3 JE.10.5:1 piston,stage two White Bros cam , Jagg oil cooler ,Arrow straight through exhaust, stronger clutch springs, 42 rear aluminium sprocket, 15 front sprocket, carb mods,52 slow jet, 158 main, standard drilled out carb and dino jet needle. Drilled out air box etc. lowered 40mm front and rear although I am 5.11.
4 It pulled like a train once it hit the cam at about 4000 rpm and could cruise at 80 all day at about 4000 to 4500 but I hated the big gap between 4th and overdrive 5th gear..
5. I sold it because it was a top heavy moose of a bike(170kg /374lbs dry ) and I always wanted an XR650L with all the engine mods.
6 I assume that I would have to import one.
7 .Hey ,thanks for listening ,.Bye the way ,.the jagg oil cooler mounted at the side is essential even here in England in the summer to keep the oil temp down when cruising at 80 to 90 mph.Drops the temp by about 30 degree .

Originally Posted by Dr LC8

Hi Cyclewizard,

thanks for all your explanations.

First of all the option of a better camshaft was suggested by my trusted mechanic. He is the most expert in XR in Rome...but beeing european he is not so familiar with the XRL model. I guess he was making his calculations on the XR600R compressio which I guess is 10.5:1 if not higher.

To summarize my bike has already a full exhaust FMF system, jetting, airfilter, wider airbox air conduit and 48 rear and 13 front sprokets.

So, starting from here, if you would suggest some mods what would you do:
1) 101mmm 10.5:1 piston?
2) XR650R carb?
3)Camshaft?

How much more in terms of power would these mods add?
Which piston would you go for?
Any idea of pricess?

Pardon my English...

Ciao

Nic

[RichNX650boy]

To Cycle Wizzard or colleagues,
How much heavier is a 105mm JE Piston than a 100mm Je piston? Just thinking about effect on revs but would not want any more that 5500 revs as would be a road bike .

Originally Posted by cyclewizard

Yes,the bike will be reliable if you upgrade to a larger piston, me I like the 105mm 710cc and 106mm 724cc kit for the tq. and power it delivers.
I think this is by far the best mod for the money.
But any high compression piston will give you a boost in performance weather it be 100mm or 108mm just not as much with the smaller forging.

For the cam I would get a mild one or use the OEM cam for reliability, it actually works quite well as long as the compression is kept between 8.3.1 and 9.5.1. If you go to a 10.5.1 piston than you need to bleed off more cylinder pressure or use a higher octane fuel.
High lift cams with lots of duration and steep ramp angles tend to wear the valve train out sooner but how much on a XRL650 is yet to be determined mileage wise. Not to many people run a steep cam on the street but me hehe. The cam is the last thing I would do because it can transfer your power band to another location and it may not be what you're looking for.
Need more info on what you're trying to do.

For the carb you can use one from an XR650R that works very well and is on the cheap, 50 to 100 dollars for that mod, jetting is 65s pilot b53e or b53f needle two clips down or a b53d all the way down and a 165 main jet or more on the main if you have many mod's done to your motor.

Pumper carbs are the hot ticket for the 650L but they're pricey, 400 to 500 dollars but well worth it in my book,another one of the better mod's for the money. You can look for a used one but there hard to find.

Exhaust, they all seem to work well on the L because the OEM one is so restrictive.

Head porting, you really only need this if you want every last bit of power out of your motor, it does make a difference on the dyno.
Stainless valves with a 3 angle cut 60/45/30 is the way to go to finish off the head work.

The first thing I would do is add an exhaust and pumper carb or a XR650R carb if your lacking on funds and see if that will satisfy your needs and go from there, I see you already have an exhaust.
The pumper carb transforms the L into another bike coming from the stock CV carb.

Add all the mod's together and you have one very mean L.......

[RichNX650boy]

To Cycle Wizzard or colleagues,
How much heavier is a 105mm JE Piston than a 100mm Je piston? Just thinking about effect on revs but would not want any more that 5500 revs as would be a road bike .
Rich NX650boy.London.

Originally Posted by cyclewizard

Yes,the bike will be reliable if you upgrade to a larger piston, me I like the 105mm 710cc and 106mm 724cc kit for the tq. and power it delivers.
I think this is by far the best mod for the money.
But any high compression piston will give you a boost in performance weather it be 100mm or 108mm just not as much with the smaller forging.

For the cam I would get a mild one or use the OEM cam for reliability, it actually works quite well as long as the compression is kept between 8.3.1 and 9.5.1. If you go to a 10.5.1 piston than you need to bleed off more cylinder pressure or use a higher octane fuel.
High lift cams with lots of duration and steep ramp angles tend to wear the valve train out sooner but how much on a XRL650 is yet to be determined mileage wise. Not to many people run a steep cam on the street but me hehe. The cam is the last thing I would do because it can transfer your power band to another location and it may not be what you're looking for.
Need more info on what you're trying to do.

For the carb you can use one from an XR650R that works very well and is on the cheap, 50 to 100 dollars for that mod, jetting is 65s pilot b53e or b53f needle two clips down or a b53d all the way down and a 165 main jet or more on the main if you have many mod's done to your motor.

Pumper carbs are the hot ticket for the 650L but they're pricey, 400 to 500 dollars but well worth it in my book,another one of the better mod's for the money. You can look for a used one but there hard to find.

Exhaust, they all seem to work well on the L because the OEM one is so restrictive.

Head porting, you really only need this if you want every last bit of power out of your motor, it does make a difference on the dyno.
Stainless valves with a 3 angle cut 60/45/30 is the way to go to finish off the head work.

The first thing I would do is add an exhaust and pumper carb or a XR650R carb if your lacking on funds and see if that will satisfy your needs and go from there, I see you already have an exhaust.
The pumper carb transforms the L into another bike coming from the stock CV carb.

Add all the mod's together and you have one very mean L.......

[RichNX650boy]

To Cycle Wizzard or colleagues,
How much heavier is a 105mm JE Piston than a 100mm Je piston? Just thinking about effect on revs but would not want any more that 5500 revs as would be a road bike .
Do you need to machine the engine casing or use a special sleeve for the 105mm piston.?
Rich NX650boy.London.

Originally Posted by cyclewizard

Yes,the bike will be reliable if you upgrade to a larger piston, me I like the 105mm 710cc and 106mm 724cc kit for the tq. and power it delivers.
I think this is by far the best mod for the money.
But any high compression piston will give you a boost in performance weather it be 100mm or 108mm just not as much with the smaller forging.

For the cam I would get a mild one or use the OEM cam for reliability, it actually works quite well as long as the compression is kept between 8.3.1 and 9.5.1. If you go to a 10.5.1 piston than you need to bleed off more cylinder pressure or use a higher octane fuel.
High lift cams with lots of duration and steep ramp angles tend to wear the valve train out sooner but how much on a XRL650 is yet to be determined mileage wise. Not to many people run a steep cam on the street but me hehe. The cam is the last thing I would do because it can transfer your power band to another location and it may not be what you're looking for.
Need more info on what you're trying to do.

For the carb you can use one from an XR650R that works very well and is on the cheap, 50 to 100 dollars for that mod, jetting is 65s pilot b53e or b53f needle two clips down or a b53d all the way down and a 165 main jet or more on the main if you have many mod's done to your motor.

Pumper carbs are the hot ticket for the 650L but they're pricey, 400 to 500 dollars but well worth it in my book,another one of the better mod's for the money. You can look for a used one but there hard to find.

Exhaust, they all seem to work well on the L because the OEM one is so restrictive.

Head porting, you really only need this if you want every last bit of power out of your motor, it does make a difference on the dyno.
Stainless valves with a 3 angle cut 60/45/30 is the way to go to finish off the head work.

The first thing I would do is add an exhaust and pumper carb or a XR650R carb if your lacking on funds and see if that will satisfy your needs and go from there, I see you already have an exhaust.
The pumper carb transforms the L into another bike coming from the stock CV carb.

Add all the mod's together and you have one very mean L.......