Jump to content

power loss at low revs


WhiteRyder
 Share

Recommended Posts

before last friday the bike was running fine, the oil warning light came on so i got some castrol semi 10w-40 which is what is in it atm and topped it up with about 180ml. i also lubed the chain. the window now shows the oil level at just under the max level. and i just noticed the chain is abit slack.


the problem is when in high gears at low revs its gutless and i have to drop a gear to overtake or even speed up. never had this feeling/problem b4.


bike is used almost everyday in all weathers. other than oil and lube nothing has changed with the bike. hasnt been serviced in 3k miles (3 months) and it has been well looked after in its life.


what is its problem?!


(bike is a 97 yammy yzf1000r thunderace)

Link to comment
Share on other sites

it doesnt feel normal in high revs either i noticed this morning doing 110mph in 3rd at 9500rpm out of 11500rpm


it does sit in the rain under a cover most nights. only got fuel from where i usually do in the last 2 months.


it seems to pull away fine in 1st without much gas, it will even creep away without any throttle still.


i will hopefully tighten my chain round my m8s soon to eliminate that possibilty.

Link to comment
Share on other sites

My guess would be your exup valve sticking, can you hear it whirr and whine after you turn the key but before you press the start button?

 

yes i can! happened on and off for about a month now.


what does that mean exatcly? how will this effect the bike?


should i head straight 2 a garage?

Link to comment
Share on other sites

My guess would be your exup valve sticking, can you hear it whirr and whine after you turn the key but before you press the start button?

 

yes i can! happened on and off for about a month now.


what does that mean exatcly? how will this effect the bike?


should i head straight 2 a garage?

 

If it does whirr and whine its the valve thats opening and shutting and is normal for it to make that noise, if you don't hear it then its probably stuck. You might even be able to see it turning. (its at the bottom of your exhaust under the engine)


The EXUP valve gives you more power at low revs by shortening the exhaust and then changes at high revs to give you more power. If they stick or the cable breaks etc... you'll notice it more at low revs than high revs. If the valve is stuck though, you won't damage the bike by riding it.

Link to comment
Share on other sites

My guess would be your exup valve sticking, can you hear it whirr and whine after you turn the key but before you press the start button?

 

yes i can! happened on and off for about a month now.


what does that mean exatcly? how will this effect the bike?


should i head straight 2 a garage?

 

If it does whirr and whine its the valve thats opening and shutting and is normal for it to make that noise, if you don't hear it then its probably stuck. You might even be able to see it turning. (its at the bottom of your exhaust under the engine)


The EXUP valve gives you more power at low revs by shortening the exhaust and then changes at high revs to give you more power. If they stick or the cable breaks etc... you'll notice it more at low revs than high revs. If the valve is stuck though, you won't damage the bike by riding it.

 

well looks like work that is above me so ill look into going 2 a garage. found this on it


http://www.thunderace.host.sk/thunderac ... owto/exup/

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Welcome to The Motorbike Forum.

    Sign in or register an account to join in.

×
×
  • Create New...

Important Information

Terms of Use Privacy Policy Guidelines We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Please Sign In or Sign Up