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XR650L decomp removal thinking

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alright so I took my decomp off my stock xr650l camshaft and I plan on welding up the oil hole but, I talked to a friends dad about it and he said he would put the decomp back on because it would have a harder time starting and i have heard that from 2 people now.

the thing is I have always heard the total opposite when talking about this particular bike. I am not sure about other bikes or models regarding decomp assembly but everything I have heard about the xr650l says that its easier to start without the decomp on.

I have an e-start xr and I know if i changed to a hotcam then there wouldnt even be an option to have a decomp for this bike so what I want to know is if anyone has an e-start only xr650l and took their decomp off and if they are having problems or not with it. I would think, logically it wouldnt have a problem starting seeing as how I was either going to put the stock cam back in with out the decomp or change to a stage one hotcam which honestly I wasnt trying to do just because I dont want a hotcam(personal preference). let me know, and I appreciate any feedback on the subject.

anyone,

anyone,

bueller... bueller....

thanks!

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so no one has any kind of input on weather or not a stock camshaft with out the decomp on would affect starting in a positive or negative way?

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Should be no trouble starting as long aa battery good - had a Stage 1 cam on my last bike and that did not have the decompresser.... just plugged the oil hole and all ok

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non issue like reduceus says, hotcams and other aftermarket come with no decomp, unless you ask for one from megacycle etc...

do a good battery replacement whenever you get te chance with a higher crank power battery or relocate with the powerful shorai, etc...type battery mods, you loose weght etc...

my ONLY advice is make sure the welder is qualified...I say this because crappy welders might arc the weld at the worst spot, like one of the camshaft lobes and any deformity will destroy your rockers in no time

I did this on my xr6, I like to think that there is less spinning mass when accelerating(jajaja) and its in fact easier to start using the manual decomp

Ive seen some xrl guys even put on an xr6 valve cover with decomp lever when doing the kickstarter mod too so they have the best of both worlds

good luck and make sure you weld the cam WELL!

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There is absolutetly nothing to be gained by removing the decompressor assembly. Do you know more than Mr Honda???

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There is absolutetly nothing to be gained by removing the decompressor assembly. Do you know more than Mr Honda???

oh snap look whose here?

yes there is but since you said so no point...huh? jajajajaja

benefits, easier "starting"( when jetted right), less rotational mass, less failures from known decomp mechanism on cam which do fail regularly after say what 30k miles? etc...

to each their own :thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup:

Edited by elsalvadorXR6

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It`s on there for a reason,this is why i went Megacycle.......it may still start great,,but it`s putting an extra load on the starter and the rotational mass you would loose will gain nothing on an engine that has this much weight on the crank and flywheel...

If it was noisy,,worn out,and you couldn`t afford to repair it ..then you could remove it i guess......i wouldn`t..

B

Edited by brianhare
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here is what I really think is the reason its there

1. its 95%percent an anti kickback mechanism.

2. since honda had some great bean counters in the nineties, they said well use the same cam the xr6 has, and put it in the xrl engine, and to save MORE money will eliminate the manual decomp on the xr6 valve cover and even save more money cause we dont use the arm, spring, tab and associated parts.

3. theeeeeeeeeeeeeeeeeeeen because these bikes are used atdifferent altitudes and climates and we dont want people suing honda because of kickbas and whatnot well just leave this little doodad on the cam since that is cheaper than making a new cam for the xrl.

thats what I think

on the xr6 there is absolutely positively no benefit in having 2 yes 2 decomp assemblies...honda is famous for redundancy and this is one case where I simply dont see why you would want 2 versions of the same thing

having said this if it working fine on your xrl with electric start there is no damn reason to have a manual decomp only

thats why you have the awesome battery mods, and relocation etc...that give you more battery power and less weight and yet still have enough cranking power for a non autodecomp cam like the xrl has(when going aftermarket like hotcam or....)

PS. BRIAN SO WHAT NO UPDATE ON THE CAM???????????????????????????????????????????????????????

geeeeeeeze

Edited by elsalvadorXR6

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thank you for responding, everything I have read or heard about the decomp for the xr650l was pretty much like this, easier to start and its not needed but then i think about kickback and whatnot and I can understand why its on there but i have already taken it off and will weld the oil hole up.

so pretty much i need to watch my starter because of the load and upgrade my battery for better cranking then.

like i said before i couldnt think of a reason why i would absolutely need it on since other higher performance cams dont have it and they start up fine. thanks for all the input.

and obviously mcma i do know more than everyone everywhere at any time or place in the world, no make that the universe. especially since i am on thumpertalk asking for opinions on what I was thinking...(thats sarcasm btw)

by the way the only reason its not on there anymore is because someone else thought it was their cam for their xrl and removed it and lost one of the springs and ball in the assembly thinking it was their cam which on his, the decomp assembly had started rattling and whatnot and he was replacing it. so now im out a decomp assembly since i left my cam at someone elses shop to get an opinion on it. people...

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Hi,

With the decompression unit removed, the motor turns over a little slower than normal, when starting, and the starter motor struggles a little bit. The stock compression is only 8.3 to, so it still turns over fast enough to start it up reliably . Later, I ran a J&E 10.25 to 1 compression piston and a big cam. Same thing, starter motor runs a little slow, but it always started. I put 30,000 miles on it, in that condition. I did buy a XR 600 valve cover. It has the manual cable operated decompression valve. Now you have best of both, use it if you need it, don't use it if you don't need. My thinking is, that you could also push start the bike with a higher compression piston, which you can't do now.

Edited by Captain Midnight
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Mine has ~50,000 miles on it and something like 35,000 without the auto decomp. I documented it somewhere, but don't have the manual handy right now.

I pressed on a sleeve before pressing the cam sprocket mount on, to cover the oil hole.

I never experienced any starter problems, but that doesn't mean I haven't shortened the life of the starter. Only time will tell.

If I ever put a kick starter on it, I will use an XR cover with manual decomp.

Edited by Onederer
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Hi can some one give me a we help I have a xr600r 1993 with a decompression lever on the bar,s I was riding . A long got up to 2gear and she stops runing . I did try to start it back up ?????? But had no compression .the decompression lever dus not feel right .. Soft as you pull it in it was never like this . Help help big pleeees

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Hi can some one give me a we help I have a xr600r 1993 with a decompression lever on the bar,s I was riding . A long got up to 2gear and she stops runing . I did try to start it back up ?????? But had no compression .the decompression lever dus not feel right .. Soft as you pull it in it was never like this . Help help big pleeees

Disconnect the cable and try it,,that fails it may be the auto mechanisms failed,,I say "may" as it could be anything..

I've outlined the removal of the auto decomp on the cam in the thread below,,you may want to keep it on the bike..If that's the case you're still going to have to go in with the scalpel to get it checked and to check the manual arm on the head and the bits inside the head cover that are actuated when you pull in the lever,,Too much work then I guess you''ll need to get someone else to do it..I also wouldn't say my manual levers that tough to pull in,,I could do it with 1 finger..

http://www.thumperta...wback-no-start/

Remember I said it may be the problem,,not that it is for sure the issue,,No one here can be sure on these things..we just guess a lot of the time.

Edited by Horri

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Thank you so much for your help . I will try this ASAP .it is just that the lever was never that slack and the bike was going well . Then just stops . No compression . It is a strange one as the xr600 ar good bikes and never mis a beat . Is there eny one that can help on this problem . I think a will be ok stripping it my self so just have a we look in the top end a was thinking mite just be poppet out . Eny help would be good thanks .... Craig

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