xr650L hotcam report

Bikes all done runs great thanks

Bikes all done runs great thanks

What is your thoughts on the hotcam?

My friend has not been able to ride the bike. It's been raining . I know it runs better then mine I still have all the smog on it. What do you guys think about changing the carb.

A pumper flat slide will give you almost instant throttle response. A little better power is noticed WITH a performance cam/hicomp piston. I picked the FCR 41. Really happy with it. No choke, not really needed with the pilot a bit on the rich side of the line. I also switched because i have no airbox(battery and electronics are in it). I run a pod filter. Pod's make CV carb tuning a real:foul: .

Took bike out today. He said likes the mid range power. He's going to the carb next Has not done exhaust yet . He heard that it did not make that big of a difference What do you think.

The carb is the best way to improve throttle response. Exhaust will help everywhere.

I have been mucking around with my jetting with about the same setup as everyone here, just finished it. I see at an elevation of about 5000ft - 158/52 - 2 turns out, runs well with the hotcam stage 1, 100mm 9:1 compression piston? The guy before me had a 140 main for some reason. It is not working... I will try new jets tomorrow! I am running it on a fully rebuilt 95 xr600r.

I have been mucking around with my jetting with about the same setup as everyone here, just finished it. I see at an elevation of about 5000ft - 158/52 - 2 turns out, runs well with the hotcam stage 1, 100mm 9:1 compression piston? The guy before me had a 140 main for some reason. It is not working... I will try new jets tomorrow! I am running it on a fully rebuilt 95 xr600r.

The jetting wont be the same in a 600R carb as it is in an 650L carb.

its not that much trouble though. the overall power gain is worth it, IMHO. maybe i made it sound like the bottom end is dead, its not. i think there is some jetting changes to deal with still. i also think that if i were to do it again i'd put the hi comp piston in at the same time.

another thing, feeling that mid - top end hit, is VERY cool!

What's required to put in the high comp piston? Does the cylinder need to be bored or re-surfaced? I'm ready for the hotcam and am wondering if the piston is worth it at this time...

What's required to put in the high comp piston? Does the cylinder need to be bored or re-surfaced? I'm ready for the hotcam and am wondering if the piston is worth it at this time...

i've been looking into a piston & cam also...

the JE Piston website mentions "Deglaze Only" for the standard 100mm 10.5:1...nothing on the Wiseco site.

...is the Wiseco considered to be a better product than the JE??? ...and why is one better??? :thumbsup:

...and i'm still not positive what if anything needs to be done since the Hotcam lacks the decomp...does an oil passage need to be blocked from the decomp to keep proper oil flow to the valvetrain???...or is that only required if u remove the decomp from the stock cam??? :worthy:

TIA,

kenny

if you completly remove the automatic decompression device you have to either shrink a sleave over the hole that are there to lube the Autodecomp device, Or weld the holes shut. when we send them off to megacycle we have them weld them up for us.

if you completly remove the automatic decompression device you have to either shrink a sleave over the hole that are there to lube the Autodecomp device, Or weld the holes shut. when we send them off to megacycle we have them weld them up for us.

so for the Hotcam Stage 1 which states "Does not use auto-decompression mechanism", "It is not possible to use the auto-decompression on the Hot Cams so do not attempt to re-install"...this is required or reccomended???

i'm looking at two different manuals, plus Hotcams installation instructions(no additional mention of the auto-decompression other than the above) and i'm lost...:worthy: i can't even identify the hole ur talking about.

also what r u thoughts on some posters suggestions on using scotchbrite pads to deglaze the cylinder to prep for high compressions piston install taking into account DIY and non-high performance motors like ur use to?

TIA

kenny

P.S. when u gunna have sum trick headers for us? :thumbsup:

JE actually has a better reputation for quality than Wiseco, at least in the automotive sector. The discussions I have read circled around Wiseco using a harder alloy that wasn't as forgiving in forced induction and nitrous applications. I haven't seen too many complains about their bike pistons, though. I plan on getting a JE when I need to replace the piston I have now.

yo kenzo - let me know what piston you get if you do it. I want to but won't until I'm certain. The hotcam stage 1 is on it's way.

Yo Yo kenzo

camshaftdecompressionholes.jpg

those are the three options that we do. First option is leave the holes alone. If you leave them alone youw will have a slight loss of oil coming out of the cam lobe holes and center support but not too bad. You might wear the lobes out sooner,turns your cam a pretty color of blurple. The second is to weld the holes up( best way). and finally make a sleeve and shrink it over the holes ( good if you cant weld but you can lathe). On some of our high lift cams we have to also cut the decompression finger off the side of the rocker because the increased lift causes it to hit the side of the exhaust lobe( not good). the same happens if you keep the auto decom installed with a higher lift cam You get clearance issues and a junk lobe. Have to finish my motor so I can make my exhaust one step at a time. For quick deglazing i use a mill with a bristile ball hone at very slow speeds but it has to have a pretty good throw to pass the whole distance. Normally I use a sunnen vertical hone on everything. Its the BOMB. unfortiunatly with all the equipment we have we do not use scotch brite to deglaze so I can help you there. I do use it if I have a tiny bit of scuffing on a piston though.

muchas gracias Senor Stepho...:busted:

i see exactly what ur talking about now :worthy: and if i'm not mistaken it is an issue the stock cam and/or regrinds of the stock cam without the de-comp mechanism...

this shud not be an issue with the Hotcams since it wud make no sence for them to add these oil passages...at least now we know wut to look for :thumbsup:

thanks for the help and keep use posted on ur bike(s)...

:blah:

What's required to put in the high comp piston? Does the cylinder need to be bored or re-surfaced? I'm ready for the hotcam and am wondering if the piston is worth it at this time...

basically wut found is a simple cleaning of the bore with a touch-up of the hone pattern is all that shud be required for lower milege bikes....can be as simple as a Scotchbite pad or 220 Grit Aluminum Oxide sandpaper with oil as a wetting agent...

for a more professional job a brush hone or ball hone like Stepho mentioned...if the cylinder shows sum significant wear or there is evidence of blow-by and/or high oil consumption i wud take it in to be measured to determine if a rebore is needed...

Wiseco seems to be the favorite choice for off the shelf XR pistons around here and i wud probably go with the herd... mooooo...

:thumbsup:

basically wut found is a simple cleaning of the bore with a touch-up of the hone pattern is all that shud be required for lower milege bikes....can be as simple as a Scotchbite pad or 220 Grit Aluminum Oxide sandpaper with oil as a wetting agent...

for a more professional job a brush hone or ball hone like Stepho mentioned...if the cylinder shows sum significant wear or there is evidence of blow-by and/or high oil consumption i wud take it in to be measured to determine if a rebore is needed...

Wiseco seems to be the favorite choice for off the shelf XR pistons around here and i wud probably go with the herd... mooooo...

:thumbsup:

Hot Cams Stage 1 Cam - Honda XR600R (1988-UP) / XR650L: http://www.xrsonly.com/content/index.php?page=shop.product_details&flypage=shop.flypage&product_id=419&category_id=145&manufacturer_id=0&option=com_virtuemart&Itemid=77

JE Pistons Honda XR650L Piston Kit - 644cc / 100mm / 10.5:1 Compression: http://www.xrsonly.com/content/index.php?page=shop.product_details&flypage=shop.flypage&product_id=3654&category_id=145&manufacturer_id=0&option=com_virtuemart&Itemid=77

I called XRs Only & this is the piston they recommended, and the cam I ordered yesterday. Hopefully a mechanical squid like me can pull this project off in a week-night or two. Thanks for the tips kenzo, I hope the cylinder looks good. I'll try to post some pics of the process in a new thread too.

Will this affect the running temperature of the bike? Premium fuel @ the pump is still enough too I assume...

u shud expect increased engine temps...more power usally equals more heat...that's why i have the oil cooler on standby

i'm so swamped with the restaurant it'll probably be a month or two before i pull the trigger on the cheapo fleabay offers on pistons & hotcam...

i'm a total nob on piston swaps...the info is wut i dug up, not from first hand experiences.

:thumbsup:

stepho, what happens when you do not plug the oil passage for the auto decompression device? I didn't and it seems okay so far, but I do notice additional crankcase pressure for some reason. I was worried this would lower the overall oil pressure but I couldn't find what anyone did with the hole so I left it open..

Thanks!

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