A forum for owners of Yamaha TTR250 trail and enduro bikes!

davecambo · Senior Member

valve clearances

davecambo · Senior Member

SEE HERE for a valve clearance checking and adjustment guide

hey guys, my bike has just clocked over one thousand KM on her, and I notice that the owners manual says check valve clearances every 20,000km or 12,000 miles. Does this mean the first check of the valves is 20,000 or is it normally done at 1,000 then 20,000. I note there is not tick in the 1,000 box for this part of the maintenance though.

Cubber · Super Guru

Dave, if it's not broken then don't fix it unnecessarily. biggrin

If the performance, economy and sound of your bike doesn't cause concern then carry on riding and enjoy it.

On the other hand, if it's rattly, uneconomic, leaky or hot then adjust things back to normal.

The instruction manual is basically a guide for new owners on what to look for to keep things sweet. A new owner may not be as mechanically sympathetic.

If your guide tells you to check and adjust a setting at certain periods then it's based on the manufacturer's vast experience.

From new a bike has to be "run in" carefully to allow various components sufficient time to bed in and get to know each other.

The new owner is advised not to labour the engine or exceed specific engine revs/speed. Doing it gradually is the key.

As they wear together the original clearances quicky become wider and if they weren't adjusted back to normal they may get too sloppy and wear much more quickly. bleh

The advice is to initially check and adjust things after the first few km/miles and return to specification. Once readjusted then the period of check/adjust can be considerably extended - the initial wear has happened and the components will be bedded together better.

The TTR Service Manual (USA version 5GF-28197-E0) has a Periodic Servicing guide that specifies checking valve clearances every 1,200 miles (2,000 km) or every 12 months. It does not have any advice to check at the Initial 100 miles (150 km).
The distances/time may be vary for certain locations and the Handbooks, for example, show differences between Australian and American machines.

Martyn

Cubber · Super Guru

Touché, this is a copy I have:-

Cubber · Super Guru

And this is the Service Manual

Image2 ().jpg

davecambo · Senior Member

so which is it, my 20,000, your 40,000 or both of our service manuals 2,000.

Cubber · Super Guru

Dave, that's the $20,000 question! biggrin

In all honesty I have never had to adjust the vales on my TTR in over 5,000 miles that I've ridden it, and they are still not rattling! wink

Play it by ear. If they evidently need adjusting then do them. If they sound OK then leave them alone and do something else.

It's obviously a job that needs to be done as necessary, it's just that not everyone's necessary is the same.

Martyn

LRJ · Senior Member

Wow! How can these numbers vary so much? 20,000 miles (let alone 24,000 miles) seems like a long time to go without checking valve clearances on manually adjustable valves. My owner's manual (North American, yr 2000) gives the 1200 mile/12 month figure. Do you think that time and experience allowed the manufacturer to reevaluate?

davecambo · Senior Member

im thinking 1,200 miles is too soon, and 12,000 is too far apart lol.

TTRfan · Super Guru

To check every 1,200 miles seems OTT to me. I am pretty sure that most TTRs will reach 12,000 miles and still have valve clearances within specification.

Brian

ronny · Member

Hi

Just approaching the 12,000 mile stage , is there a pictorial service link, so i can carry out my Valve Clearances.

TT-R250M · Super Guru

Checking valve clearances is much the same on any bike. You should be able to use any of the links below and achieve this. However, the manual has a detailed version of this and you should have it sitting in front of you before doing anything.

Valve specs are .09mm-.17 intake and .19-.27mm exhaust. You need feeler gauges, preferably ones with a 45 degree bend.

http://www.thumpertalk.com/wiki/_/checking-adjust-valve-clearances-06-yamaha-yz250f-r306

http://www.thumpertalk.com/topic/607999-adjusting-the-valves-ttr250/

http://www.youtube.com/watch?v=yNJ9Da2dF-Y

http://www.youtube.com/watch?v=1lrH1U4FnRY

There are HEAPS more too.

Jarrah

-- Edited by TT-R250M on Tuesday 17th of December 2013 02:47:18 PM

Cubber · Super Guru

There are six pages in the TTR service manual detailing valve clearance adjustments.

Beware - it entails removal of the front head/frame steady AND the exhaust sytem, amongst other things. biggrin confuse biggrin

This is page 3-6

This is page 3-7

This is page 3-8

This is page 3-9 which details the shim size requirements.

This is page 3-10

And this is page 3-11

On the other hand - you could always take the bike to a mechanic and ask the professionals to do it. biggrin biggrin

Martyn

ronny · Member

Thanks guys

TT-R250M · Super Guru

Cubber wrote:

Beware - it entails removal of the front head/frame steady AND the exhaust sytem, amongst other things.

Martyn

Not sure why they say to remove the exhaust in this case and the other thing is that the engine should be absolutely cold before checking (3~4 hrs.).

If you need an offset feeler gauge set, see here- http://www.ebay.co.uk/itm/S0515-SEALEY-FEELER-GAUGE-26-BLADE-OFFSET-DUAL-MARKED-BRAND-NEW-SEALEY-TOOL-/400483990568?pt=UK_Baby_FeedingSets_RL&hash=item5d3eb4bc28

Jarrah

chrisstdt · Senior Member

Ive just checked mine earlier in the week and i struggled with my straight feeler gauge il have to get me a set like that

TTRfan · Super Guru

Never had a problem with the straight feeler gauges. But check the sizes on any set you buy. The smallest of the Seeley gauges is 0.005in. Ideally you want a set that includes the individual sizes from 0.001" to 0.010" as well as the bigger ones.

I think these are the ones I use - http://www.ebay.co.uk/itm/0-02-to-1mm-17-Blade-Thickness-Gap-Metric-Filler-Feeler-Gauge-Measure-Tool-/390668465023?pt=UK_Measuring_Tools_Levels&hash=item5af5a7b37f

Brian

TT-R250M · Super Guru

TTRfan wrote:
Never had a problem with the straight feeler gauges. But check the sizes on any set you buy. The smallest of the Seeley gauges is 0.005in. Ideally you want a set that includes the individual sizes from 0.001" to 0.010" as well as the bigger ones.
I think these are the ones I use - http://www.ebay.co.uk/itm/0-02-to-1mm-17-Blade-Thickness-Gap-Metric-Filler-Feeler-Gauge-Measure-Tool-/390668465023?pt=UK_Measuring_Tools_Levels&hash=item5af5a7b37f
Brian

TT-R250M wrote:
You need feeler gauges, preferably ones with a 45 degree bend.

I didn't say that the offset gauges with a 45 degree bend are needed, just that they are preferable. The reason being that if using the usual gauges, you have to bend them to fit them in to check clearances. While doing this you must make sure that the feeler gauge does not go in on an angle as this will give you a false reading.

Jarrah

Truxx · Veteran Member

Valve adjustment shim advice

LoopSoosStroop · Veteran Member

Do you have the service manual? They explain it quite well there. Yes, I would go for an 180 in your case.

What km is your bike on now? First time doing shims on it?

Truxx · Veteran Member

Hi

I ended up buying 180 and 175 shims just incase. 180s done the trick so I'll have spares ready for next time

no idea about mileage. It says 2500 on clock but I doubt that's right

mileage on mot only goes to 2011 so I'll probably never know for sure although I don't think it's been apart before today as there's no signs of scuffs to any bolts where tools have been used so it's probably it's first valve check.

Fladdem · Senior Member

RE: Valve Clearances

TTRfan · Super Guru

Hi there

Did you clean up and lap the valves in when you did your refresh? If so, that can alter the clearances, usually by reducing them. Otherwise, unless you are very careful it is possible to swap the valves or camshafts over.

I find that it is worth turning the engine over a few times to settle the valve gear in before doing the measurements.

It is also possible that the exhaust shims aren't seated properly which will give those tight readings.

I started to look at the shim sizes but my brain isn't functioning properly so I am off to bed. Hopefully someone will step in to fill the gap wink

brindabella · Senior Member

Fladdem, for what its worth, I get the same suggested pad sizes as you when I plug your measurements into the chart.

I would have thought your measured clearances not far enough out of spec to represent anything other than normal wear - not that I am any expert on this.

In fact, I would not be surprised if a brand new bike might have clearances appearing slightly out of spec, as it is hard to get a super precise exact measurement.

With your 0.076 and 0.102 measurements, obviously you are using an imperial feeler gauge (ie 3 thou and 4 thou), but maybe the ideal way would be to use metric feeler gauges and stack two blades if needed to get a "go" for the minimum (eg 0.19 for the recommended clearance range) and "no go" for the minimum of the next range (eg 0.28 for that same range).

The range intervals in the chart are all pretty small (and maybe hard to choose between two adjacent ranges when measuring) so it would seem hardly necessary to "second guess" the chart for edge cases.

By the way, the chart shows pads with numbers going up by 005, but maybe someone else knows whether the original installed pads can actually have numbers such as 186 (ie not multiples of 5) , even though you cannot get a 186 replacement pad?

TTRfan · Super Guru

I use a laminated guide with the cam lobe positions and clearance ranges written on it along with an essential bit of kit - a set of metric feeler gauges with individual gauges from 0.02mm to 0.10mm and then in stages of 0.05mm.

As brindabella says, stack two blades where necessary.

Mr Yamaha had his own special supply of shims that increment in units of 1 that aren't available to us mere mortals

Fladdem · Senior Member

Correct, I am using Imperial feeler gauges, they were my granddads, he left me a load of tools. How do I know if I have put the wrong camshafts on? Is there a distinguishable way of picking them apart, i.e. if I measured cam lobes, what are the measurements for them? When I took them off, I just put them in the box of bits, assuming that the exhaust had E on the sprocket and Intake had I, but both sprockets are the same, which I didn't notice taking them off. disbelief

I will investigate the shims, to check they are square on the exhaust valves, I was turning the engine over a few times before measuring clearances. With regards to grinding the valves, I did a bit of grinding on the exhausts, considering they looked like this:

I looked at my notes today when I was less tired and got the same results, so I should have the valve clearance table reading sorted. Before I order some valve shims, I'm going to have to double check they're sitting correctly.

Thanks a lot!

TTRfan · Super Guru

Fladdem wrote:
How do I know if I have put the wrong camshafts on? Is there a distinguishable way of picking them apart, i.e. if I measured cam lobes, what are the measurements for them? When I took them off, I just put them in the box of bits, assuming that the exhaust had E on the sprocket and Intake had I, but both sprockets are the same, which I didn't notice taking them off.

Both camshafts have the same part number so the way to tell which goes where is to mark them as you take them off. It would be interesting to know if the clearances are nearer what you expected if you swapped them around wink

Brian

TTRfan · Super Guru

I have updated the "How To" web page and hope it is an improvement but, as always, I appreciate feedback, criticism or suggestions for improvement!

See here