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Re: Honda CBR 250R
How do i find out if i've blown my shims? Are there any symptoms that can be easily identified?
How do i find out if i've blown my shims? Are there any symptoms that can be easily identified?
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Re: Honda CBR 250R
What do you mean 'blown' ! As in 'blown to bits' ? Or if they are no longer in spec for the right valve clearance ?Originally posted by Jon Niranjan Paul View Post
A shim looks like a small button cell (like the ones that come in wrist watches). And the purpose of the shim is to maintain the right valve clearance. On bikes like say the splendor, pulsar, the valve clearances are adjusted using the nut/screw.. while on bikes like the cbr, ktm this is done by changing shims.
Over time due to wear and tear the valve clearances go out of spec and need to be measured and adjusted to spec. On a shim type bike, you will need to change the shim to the appropriate sized one to get the clearance within spec. Each valve has it's own shim, so depending on how many valves are out of spec you might need as many shims (or fewer if you could reuse a shim on another valve).
And coming to 'blown' , if you shim broke apart , there noisy valve clatter, stuck valves.. smashed piston, chewed up camshaft.. finally a ruined engine!Comment
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Re: Honda CBR 250R
I haven't faced it personally, but guys who have done shim replacement had complained of a jingling noise from the engine, like small coins jingling in a bowl.Originally posted by Jon Niranjan Paul View Post
Edit : I have faced a jingling noise after a hard ride ever since I bought the bike, but it was always temporary. I presume my bike has self healing shims. [emoji6]Comment
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Re: Honda CBR 250R
Same here, I just did a 1200km+ ride this past weekend, and seem to have some sort of jingling noise. It has reduced today, but is still definitely there. Opened up the bike as much as i could, checked clearances and everything seems normal according to the specs in the manual. However i don't have the tool to open the crank case. If the clearances are intact, the shims are theroretically intact right?
Also noticed a lag in power delivery, and the knocking in 4~5k rpm was absent for 6-7 months, but has come back now. Bike struggles to do anything over 110. Will be cleaning the throttle body and washing the tank and changing the petrol filter this weekend. Hopefully it's just fueling problems w.r.t power delivery.
EDIT: Shims are ok. Just checked em. Te damn noise is still there though. Checking the timing chain now.Last edited by Jon Niranjan Paul; 12-28-2016, 11:52 PM.Comment
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Re: Honda CBR 250R
I would like to gain some insight and experience wrt the CBR. If you don't mind me asking, where are you put up in Kerala?Originally posted by Jon Niranjan Paul View PostComment
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Re: Honda CBR 250R
Originally posted by leech View Post
Actually based in Bangalore, originally from Chennai. Honestly speaking, I'm no expert over the CBR, I just refer to the manual and this forum for clearing my doubts! But hey, do PM me or WA me anytime (9940134533). Would be glad if i can be of any help at all.Comment
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Re: Honda CBR 250R
Actually, a guy who can check valve clearance is way more knowledgeable than me. Would love to see it being done, but don't have the guts to do it myself. Whenever I take something apart, there is always some extra pieces left over after I put it together. [emoji19]Originally posted by Jon Niranjan Paul View PostComment
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Re: Honda CBR 250R
S1d has already explained excellently about shims. Shims are made of one of the most strongest materials used in your bike and don't worry they aren't going to blow up! After reading your issue, I would just say to recheck the valve clearance one more time. Try to measure out clearance by a short and pointed feeler gauge this time. Saying this on the basis of personal experiences. There is no room for longer feeler gauge and hence more chances of incorrect measurements. Adding some pictures for shim references.Originally posted by Jon Niranjan Paul View Post
A shim
Shim in a micrometer
Used shims - you can clearly see round mark on second from left.
Packet of a CBR shim
Edit: By the way after a long haul, you may hear shim noises. I recently did 930 Km in a day on my CBR. There was little jingle which I heard when I removed my helmet after reaching home, but it went away next morning after cooling down of engine over night. I could expect that after such a long haul. Hope your power issue is related to bad fuel only!Last edited by arvstreetracer; 12-29-2016, 01:00 AM.-----
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ARVIND K. YADAVComment
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Re: Honda CBR 250R
[QUOTE=arvstreetracer;1268299]S1d has already explained excellently...[\QUOTE]
Thanks
Thanks arvind. I checked with a normal feeler guage (the same one used in the SVC, mech is a close friend of mine), the clearances are normal. Need to check the timing chain tomorrow. It's OCD with the motorcycle, my mind cannot just let it go
. WIll keep this thread posted.
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you know what, my dirty secret is that i take photos of every part i remove before i remove themOriginally posted by leech View Post
. Easier to cross reference in case of doubts!!! And you always have the manual too, this is just insurance in case my manual confuses even more.
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Re: Honda CBR 250R
Dominar is going to kill CBR sales? I see lot of ppl going gaga over the bike, I understand because of the price, I'm interested to see what HMSI do?as it is CBR sales were super low , probably introduce the 300? I have my doubts on the 250rr making it here , but certain things like quality, engine life, Honda will be on top, only time will tell how bajaj does, here's a few pics of my ceeber at 28000kms after 2 years, changed chain sprocket set about 2000kms back because my maintenance of the chain was non existent in the first 10000kms, still I'm very pleased with the bike, I'm also curious has anyone tried MRF masseter? Its suppose to offer better wet n dry grip, wet grip was non existent on mrf tyres before.
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Re: Honda CBR 250R
I believe though some people will opt for Dominar over CBR due to price and power ratio but experienced and more matured riders will go for CBR due to its long term reliability.Originally posted by Deathwing View Post
And selective people will definitely go for Dominar as that's a new launch with lot of new cosmetics to offer with a naked look. So let the time talk what will happen and stay happy with CBR till the day we settle for a bigger upgrade than 250cc single cylinder.
BTW, if I'm not wrong your model is a 2013 full black one. And thanks for sharing pictures, it's always good to see CBR pics when it's in used condition and maintained.Last edited by hypheni; 12-29-2016, 11:45 AM.Comment
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Re: Honda CBR 250R
Guys, Any ideas on the issue I reported about the chain?
Here is by ride after 5.5 years but only at 18k km.
Last edited by kannanmr16; 12-29-2016, 05:19 PM.Comment
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Re: Honda CBR 250R
[QUOTE=kannanmr16;1268383]Guys, Any ideas on the issue I reported about the chain?
Here is by ride after 5.5 years but only at 18k km.
Check the rear axle alignment if it is aligned correctly. You may figure out by marks on chain adjusters. Most likely it seems what VJ has indicated in his comment against your query. If so, wash it or soak in motor oil. Wash it with diesel or motor oil. I personally avoid kerosene. WD40 is based on kerosene too, but it would be costly item in comparison to a liter of diesel. Mine is at 24k km. Recently observed chain was making noise. Upon checking it, found that some links were too tight and chain was tight at some point as well as loose at some point. Because of this uniform slack wasn't maintained. Washed it with motor oil and tried to rotate each link till it got easy to some extent. Readjusted slackness at tightest spot - figuring out by moving the wheel multiple times. Now that particular chain noise has vanished, but it's not silent.
Last edited by arvstreetracer; 12-29-2016, 07:19 PM.-----
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ARVIND K. YADAVComment
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Re: Honda CBR 250R
Sorry should have included more details. This chain and sprockets are relatively new. Have about 7k km on them, could a link be a problem so soon. This problem was present to a little extent even on the day I had the chain replaced. This issue was also there on the old chain and the reason I changed it. That was my initial assumption, so I thought it could not be the chain itself, but alignment or slider fault.Originally posted by B7ACKTHORN View PostYes, some bikes have their bar end weights being able to rotate that's completely normal. Even if you turn to tight them, you might find them they are already torqued to the max. Nothing to worry. Most CBR's bar end weights have either one or two, that rotates.
What I infer from your video is that a particular link has jammed, meaning the rollers are jammed, in that, they aren't rolling and following the other rollers evenly, that's why there is a jump that you see. Use WD 40 or kerosene, rinse them for half to one hour, clean them thoroughly with a rag, rotate the wheel by hand and observe the chain links for any tight spots, use WD 40 if required and then lube the chain, after going for small ride.
Cheers!
VJ
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Re: Honda CBR 250R
[QUOTE=Jon Niranjan Paul;1268302]i hope you don't end up messing with the timing and are checking the clearances at the tdc of compression stroke on a cold engine.Originally posted by arvstreetracer View PostS1d has already explained excellently...[\QUOTE]
Thanks
Thanks arvind. I checked with a normal feeler guage (the same one used in the SVC, mech is a close friend of mine), the clearances are normal. Need to check the timing chain tomorrow. It's OCD with the motorcycle, my mind cannot just let it go. WIll keep this thread posted.
you know what, my dirty secret is that i take photos of every part i remove before i remove them. Easier to cross reference in case of doubts!!! And you always have the manual too, this is just insurance in case my manual confuses even more.Comment
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