Advice please

[Chaz]

Good morning Gentlemens!
I’m seeking advice for a recent problem with my bike.
Problem: in acceleration I can feel ( you know that motorcycle its a feeling thing!) a step in the beginning of the acceleration. Like a slow engagement ...

Here what I have check:
- valves was done 33000KM ago along with plugs.
-I have clean the foam air filters
I have found a cracked vaccuum port on the intake.
-I have fill the tank with fresh premium gas.
-I have cleaned the throttle linkage like the « jumpy throttle fix » post.
———-
What I suspect:
-Worn rear shock , I’m waiting on a new unit this week . Maybe the rear wheel slip on the road a moment in acceleration?
- Worn clutch? But seems to works nicely.
-Oil? Its almost fresh but I have change for 10-50 semi synth...don’t know...

 

[gv550]

Have you balanced the throttle bodies by adjusting the idle air screw? While you are at it open them 3/4 turn and rebalance.

 

[Chaz]

Have you balanced the throttle bodies by adjusting the idle air screw? While you are at it open them 3/4 turn and rebalance.

No. The engine seems to run fine with consistent idle... I’m a bit scared to mess with that!

 

[Jlq1969]

spark plugs ??? ..... a worn spark plug changes (delay)the ignition point a couple of degrees
and the moment where it is most noticeable is at the start, and in accelerations
or maybe moisture in a coil, and it causes part of the spark to be lost against the engine, instead of going to the spark plug

 

[gv550]

No. The engine seems to run fine with consistent idle... I’m a bit scared to mess with that!

Don't be scared! Throttle body balance (synchronization) is required maintenance every 6000 kms and if yours has never been done that would be the first thing to do. Even though you think the bike idles fine now, proper balance will improve idle and throttle response, and opening the screws 3/4 turn is a well accepted practice to reduce the flat spot you are experiencing.

Edit..... I also recommend replacing those foam filters for the proper Yamaha pleated paper filter.

 

[EricV]

How recently have you noticed this? After winter storage, or??

Do you feel the same thing in both S and T modes? And how are you accelerating when you notice this, slowly, briskly or Whack the throttle wide open?

Air, Fuel, Spark - It's related to one of those things.

You seem to have checked the Air area fairly well. A throttle body sync won't hurt, if anything, just to see if they are off or not. You need a vacuum tool for that. Maybe a friend has one you can borrow? Have you verified that the air passage from the front to the air box is clear? Every now and then birds like to get stuck in them or mice make nests over the winter if you store the bike. The small hose on the opposite throttle body also can crack over time.

Fuel - Crud in the tank and a dirty fuel filter, (tea bag style inside the tank is our only filter), can cause this. Have you done a visual check with a flashlight to see if there is crud in the bottom of the tank? Ideally, you'd remove the tank and pull the fuel pump out to really check/clean the filter. You can get replacements off ebay, but Yamaha doesn't sell a direct replacement part, only the entire pump. There is info on the forum too, do a search if you go down this road.

Spark - Plugs, water in the plug well, corroded heat shield around the coil stick and other things could cause this too.

While you're checking things, check the battery cables too. A loose ground or batt cable can cause funky things too.

I'm quite sure I've forgotten other things to check, but we have a good group of people here that will help.

 

[PhilPhilippines]

Good morning Gentlemens!
I’m seeking advice for a recent problem with my bike.
Problem: in acceleration I can feel ( you know that motorcycle its a feeling thing!) a step in the beginning of the acceleration. Like a slow engagement ...

Here what I have check:
- valves was done 33000KM ago along with plugs.
-I have clean the foam air filters
I have found a cracked vaccuum port on the intake.
-I have fill the tank with fresh premium gas.
-I have cleaned the throttle linkage like the « jumpy throttle fix » post.
———-
What I suspect:
-Worn rear shock , I’m waiting on a new unit this week . Maybe the rear wheel slip on the road a moment in acceleration?
- Worn clutch? But seems to works nicely.
-Oil? Its almost fresh but I have change for 10-50 semi synth...don’t know...
View attachment 80610View attachment 80611View attachment 80612

Am I right in saying that if it is a kinda "fluffy" feeling as you accelerate it may be the vacuum hose?

 

[Chaz]

Don't be scared! Throttle body balance (synchronization) is required maintenance every 6000 kms and if yours has never been done that would be the first thing to do. Even though you think the bike idles fine now, proper balance will improve idle and throttle response, and opening the screws 3/4 turn is a well accepted practice to reduce the flat spot you are experiencing.

Edit..... I also recommend replacing those foam filters for the proper Yamaha pleated paper filter.

I’ll be happy to try sync the TB if you can point me exactly How to.
About the foam filters you don’t like them? I tought they were good stuff. I will buy a new paper filter soon.
I found another possible cause :
The rear brake pad shime was stuck between the piston and the pad , forcing the pad against the disk...

 

[Chaz]

Am I right in saying that if it is a kinda "fluffy" feeling as you accelerate it may be the vacuum hose?

I really don’t know!

 

[Chaz]

Hi,
I have this after a short and mild off road day last week . No water crossing but I have hit a few small puddles...

Air box is clear from any intrusion.
I will try to sync the TB but I have to buy a vaccuum calibration tool ( Motion Pro?) .

Next thing I’ll dig in the plugs area to check and clean everything ...I hate that they are tuff to reach!
I just come back from a small spin and it seems to perform better. Maybe it was only the rear brake shim causing that problem?
(see last picture that I’ve post)

 

[Longdog Cymru]

Edit..... I also recommend replacing those foam filters for the proper Yamaha pleated paper filter.

I agree, if you prefer not to use the stock Yamaha paper filter, then got for a K&N oiled foam filter or similar, but those foam sock type filters look a little restrictive to me. You have a 1200cc engine and it needs to pass a lot of air through.

 

[EricV]

The foam filters are great for high dust environments, as long as you keep them clean and oiled. Weren't these OE in Australia?

The brake issue could have been what you were feeling. I like to use some brake grease on the back of the shim where it fits against the piston, and between the shim and back of the pad. Same on the other side where the shim fits against the caliper. I use synthetic brake grease, but any auto parts store will have it in both small packets for one use and a squeeze tube.

On the spark plugs, I've found it's much easier to get to the far right, (throttle side), coil bolt from the front, over the exhaust, with a box wrench. A ratcheting box wrench makes this easier too, but isn't necessary.

And FYI - some people choose to un-clip the wire from the coil pack, but this is not necessary to get the coil pack out of the plug well. You may also want to mark your wires 1,2,3,4 so you put them back in the correct position. A couple can swap if you're not paying attention. I used some label tape, but just temp job with some painter or masking tape does the job too.

If you notice corrosion on the far left spark plug, (clutch side), that's not uncommon on Gen I bikes. Some put a light bead of silicone RTV around the area that fits against the valve cover to seal it better. I've read of people just using some grease there too. Look for arcing evidence on the heat shields on the coil sticks. If you see a lot, or a lot of corrosion, post about it.

 

[Chaz]

Thank’s a lot for all your knowledge!
I let you guys know the end.
Might take a while because I’m « dad on duty full time »because my girlfriend is working 7/7!

 

[Chaz]

UPDATE.

I bought 2 vacuum gage for 60$ and hook them to the bike. Its needle gage type so its kind of hard to read but you can see where it stops most of the time.
I can see that the TB had been adjust in the past because I found reference mark on the TB and was already back a 3/4 on the right side. I back approx each TB 1/8 of a turn each. I will test drive the Super T later and I’m hoping it will help.
I don’t know how much vacuum pressure the TB make but I settle around 17 in HG on the dial.

 

[EricV]

What you're looking to do is balance the two TBs so they have the same reading. Most people are using a sync tool like CarbTune or a Motion Pro unit where it's easier to visually see the balance or lack of. Those units are buffered to minimize the bouncing. What you're using is absolutely fine too. You can make your own up with tubing like THIS.

This is great though, you learned some new things about your bike. More vacuum flow isn't always a good thing, but sometimes it does help. Many found the stock reference side with the paint mark almost completely closed from the factory, thus the current reference of 3/4 turn out.

 

[Chaz]

Just came back from a short road test and I pretty happy with the results! So smooth and precise everywhere. I think the engine rev a bit slower when cruising and the overall sound change a little. It sure gain some finesse! Tenere love is back!

—-THANK YOU GUYS!—-so much good and precise info on that forum! Its so fun to learn and do your own wrenching instead of trying to explain your problem at a mechanic shop!

 

[WJBertrand]

Revs at any given speed will not have changed. Speed and RPM relationship are mechanically locked by the gear set ratios in the drive line. An exception would be a slipping clutch, but that would cause higher, not lower revs.


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[Chaz]

—Final update—
Finaly had some time to complete a deeper check up and got all my spark plugs and new air filter.
-I’ve change all 4 sparkplugs , clean all the coil and grease with dielectric the metal band (minimal rust on 3 )and top where it seats , found some water in the second from the right hand side...
-change the air filter with An Hiflo filter.
-And resync the TB with a proper glycerin filled vaccuum gages. Perfect.
Bike runs precise and sounds good, pulls hard. Nice!
thanks again for the info gentlemens!

 

[~TABASCO~]

Everyone rides different- depending on your style it might be slipping the clutch a bit more than most. I think yamaha dials in a bit of this for “smoothness” for the average guy. One day I would suggest throwing in a Barnett pressure plate. Much better feel and performance. Only then can you personally feel the before and after performance of this plate.

side note: this is a great upgrade for any Tenere rider. But if you ride any off road I would highly recommend it.

 

[Chaz]

Everyone rides different- depending on your style it might be slipping the clutch a bit more than most. I think yamaha dials in a bit of this for “smoothness” for the average guy. One day I would suggest throwing in a Barnett pressure plate. Much better feel and performance. Only then can you personally feel the before and after performance of this plate.

side note: this is a great upgrade for any Tenere rider. But if you ride any off road I would highly recommend it.

One day if I’m keeping the bike I will change the clutch basket because the vibes at 3k rpm are really annoying ( 700$ Can here!) Hinson clutch plate (290$ can here!!)...I don’t know how (or don’t understand how) it makes the bike Perform or feel better...
I don’t think I drag the clutch a lot , maybe more off road? For now I got 90 k km on it and the clutch engagement feels ok.
Ealier this spring I got a Klim kit ...This is big bucks for me if you add the plates of the bike( Its kind of pricey here!!!) ,normal maintenance and a rebuild shock . I try to keep the expenses in the farkling zone low but its on my list in a near future!