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Some help with valves

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Hi guys just signed up so i`m new be gentle lol

I`ve spent some hours trying to sort out and research my problem but cant seem to find good advise so if someone could help or give advise plz do

 

I own a 2007 honda crf 250 r in very good condition and i keep her that way anyway my problem is the bike is very hard to cold start but starts easy when hot normally within 2 or so kicks

so i decided to check the valve clearance just encase and as a general inspection of things.Now my exhaust side is spot on spec but my intake side i cant measure because my feeler gauge doesn't want to slide in so this is telling me the intake is way to tight, now my actual question is if i cant measure the clearance how am i to determine the shim i should get...or should i take the big ouch and replace valves and re seat?

 

Thanks in advance for any help or advise 

 

ps. i am mechanical minded and able so getting technical is okey ;) 

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Hi guys just signed up so i`m new be gentle lol

I`ve spent some hours trying to sort out and research my problem but cant seem to find good advise so if someone could help or give advise plz do

I own a 2007 honda crf 250 r in very good condition and i keep her that way anyway my problem is the bike is very hard to cold start but starts easy when hot normally within 2 or so kicks

so i decided to check the valve clearance just encase and as a general inspection of things.Now my exhaust side is spot on spec but my intake side i cant measure because my feeler gauge doesn't want to slide in so this is telling me the intake is way to tight, now my actual question is if i cant measure the clearance how am i to determine the shim i should get...or should i take the big ouch and replace valves and re seat?

Thanks in advance for any help or advise

ps. i am mechanical minded and able so getting technical is okey ;)

Hi I'm cas you should join team tt and speak to a guy who calls himself chokey.

He dam near knows everything about everything he's a very smart man.

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Hi guys just signed up so i`m new be gentle lol

I`ve spent some hours trying to sort out and research my problem but cant seem to find good advise so if someone could help or give advise plz do

 

I own a 2007 honda crf 250 r in very good condition and i keep her that way anyway my problem is the bike is very hard to cold start but starts easy when hot normally within 2 or so kicks

so i decided to check the valve clearance just encase and as a general inspection of things.Now my exhaust side is spot on spec but my intake side i cant measure because my feeler gauge doesn't want to slide in so this is telling me the intake is way to tight, now my actual question is if i cant measure the clearance how am i to determine the shim i should get...or should i take the big ouch and replace valves and re seat?

 

Thanks in advance for any help or advise 

 

ps. i am mechanical minded and able so getting technical is okey ;)

 

If you have a int valve that has no clearance there isnt any sure way to know exactly what size shim to install to get the correct clearance the first try.

I usually remove and measure the shim and just reduce the shim size by .004 -.007" and after re installing the cam and re measuring you should be close and maybe even at the clearance spec you want, but often you need to make a final adjustment from that point to get to the exact clearance spec you want.

 

Just in case you havent seen this yet here is a link that might help you make the valve adjustment.

http://www.thumpertalk.com/topic/151755-how-to-check-and-adjust-the-valves-on-your-250-wpics/

 

BTW welcome to TT!

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If your shims are metric and your feeler gauges are standard like mine are just go by the rule of thumb .05mm = 2 thousandths. So if you can't fit the a .002" feeler gauge try going with a shim that is .10mm smaller that way you will be increasing your clearance by 4 thousandths. Since the spec is .004-.006" for the intake that should put you pretty close

 

 

Just a fyi if your intakes have no clearance it's time for a valve job... you can adjust them but it won't be long before they tighten up again.

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If your shims are metric and your feeler gauges are standard like mine are just go by the rule of thumb .05mm = 2 thousandths. So if you can't fit the a .002" feeler gauge try going with a shim that is .10mm smaller that way you will be increasing your clearance by 4 thousandths. Since the spec is .004-.006" for the intake that should put you pretty close

 

 

Just a fyi if your intakes have no clearance it's time for a valve job... you can adjust them but it won't be long before they tighten up again. 

thanks i think ill go by this makes sense the only problem with this all is i have to go buy the shims and can turn our to a expensive exercise buying the whole time to get the right clearance they charge us a fortune over here for parts  :cry: ...oh the clearance on my bike is 0.12mm i think thats 0.05'' our feeler gauge for some reason doesn't go smaller than that so ill have to go buy a special one maybe?

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If your shims are metric and your feeler gauges are standard like mine are just go by the rule of thumb .05mm = 2 thousandths. So if you can't fit the a .002" feeler gauge try going with a shim that is .10mm smaller that way you will be increasing your clearance by 4 thousandths. Since the spec is .004-.006" for the intake that should put you pretty close

 

 

Just a fyi if your intakes have no clearance it's time for a valve job... you can adjust them but it won't be long before they tighten up again.

i was thinking it was time for a valve job but i had a chat to the previous owner he had the head done professionally at Honda not more than 12 hours ago and i have not been abusing the bike i never pin it to be honest im a very passive rider not comp,he gave me the receipt of what was done and it was a full on top end job....

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go buy feeler gauges that go by the thousandths and don't skip numbers... .004 is still in spec

 

also you can get a hotcam shims kit with just about every shim imagineable for 90 bucks. Only thing about those is they go in .05mm/.002" increments while you can get them from honda in .025mm increments

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