hi everyone
i have 1998 vtr 1000f

i had a problem for a few days with clank like several forum members described on lower revs 2000-3000 rpm. i read few posts and kept on driving to see if its me, or something is really wrong with engine. btw this is my first superbike and i donīt have much experience.
unfortunately something happened this morning on my way home from work. i was passing over some bad section of road,and i hit the bump and clunk instantly became louder and now not only at lower revs but constantly . i turned off a bike to have look around, did not know what to do. than i started the engine the clunk is still there and i drove myself home.
there were no lack of power i even pushed it to 6000rpm briefly and bike behave as before except that horrible noise . no temperature rise no cracks on exhaust system no water-oil mix no dark smoke from exhaust

please tell me what to look or if someone had that kind of trouble or heard of it

thanks

 

hmmm....well i would stop riding it or tuening it on at all. then drain your oil and look for shiny bits in there. if so likely a bearing has failed. also you may wanna check your timing.

 

well the worst has happened

first the cct failed, than i hit the bump and chain jumped over cam gears and now i have a bent valve. i replaced cct and set timing that was way out of right place and started engine it worked but i do not have compression on front cylinder , gases are returning in to air box so i guess the intake valves are gone

i hope another bikers will learn from this when you hear clunk turn off engine and check first the cct.

one question: is it possible to take off cylinder head without detaching engine from the frame and is there anything else that i have to know before i commit this operation

thanks

 

Simone-sorry to hear about your engine and thank you for the advice. I have not done it but I recall reading in the shop manual that you can remove the heads with the engine still in the bike. Can you please tell me what model year your Superhawk is and how many miles you have on it? Thanks-Mort

 

Absolutely. This is much easier than taking the engine off the frame, as the frame is attached to the rear swingarm and the whole bike needs to be disassembled/suspended to do it. Nothing special to know- take off parts that are in the way. Oil cooler can be detached from the frame, carbs removed (but I like to keep the hoses on the carbs), etc. Loosen major bolts in criss cross pattern. You'll need new head gaskets, but I think those are the only ones to replace...

 

its 1998 honda vtr1000f 37000km so its says but i wouldnt be surprised if it is much more. fake mileage is common in my country. bought it this february it worked fine but i was full not to check cct when i suspected its failure.

 

They all do this regardless of year and miles. The lowest CCT failure was at 1500 miles, and the highest I have heard of was over 50k. Just replace the CCTs with manual ones and be done with it.

 

thanks 7moore i assume that you have done this before, so any advice is welcome

 

Might be easier and cheaper to source a second-hand font head and replace yours. Whilst your at it check valve clearances and replace as needed shims. Plus get some manual CCTs Apes or similar ASAP.

See the Workshop knowledgebase section to download the Honda VTR Service manual PDF and also the stickied thread on how to install manual CCTs.

 

I just finished putting it back together. Like an hour ago

This may help a bit- there are a couple of pics...

https://www.superhawkforum.com/forum...-firing-24990/

I did forget to mention a couple of things, you want to make sure you're at TDC for the correct cylinder when you take the cams/cam covers off- With the valve covers off you can see the cam lobes (there are pics about half way down). Turn the crank so the lobes are facing symmetrically outward for the front cylinder and then symmetrically inwards for the rear cylinder and then remove the cam covers. Otherwise the valves are pressing upwards and you may mess something up....

Once you get those off, you have to take tension caused by the CCT's. If you have manual ones, you just loosen them a bunch. If you have OEM ones, you'll have to remove them (and get a replacement gasket). This is also a great opportunity to replace them with manual ones b/c setting the tension is very easy with the valve covers off. Then you can take the cam chain off and pull the cams out.

Also, (this gets a paragraph to itself) Keep everything labeled and organized- I use zip lock bags or containers- b/c it has to go back in the same spot. No mixing or matching parts as the tolerances will be wack if you do.

 

Ooh, time for an update on your main thread on how it runs??

 

Yessir!

 

here is the problem.
on images you can clearly see that there is space between valve and valve seat. exhaust are more damaged than intake valves i am not shore that intake valves are damaged at all because when i try to press them they slide perfectly back and forth however that is not the case with exhausts.

but anyway i will replace them all just in case

 

Yep, it is usually the exhaust valves that go when a CCT fails.

Check out your costs for repair, and also look on Ebay - salvage yard etc for a replacement head. And be sure to change to Manual CCTs when you are done so that it doesn't happen again.

 

Assuming the piston isn't destroyed from something like.this are there any damage possibilities to the crank or bearings?

 

not that i have noticed. the valve is weakest part i assume next would be chain not cam bearing, but who knows ill check tomorrow i feel depleted from kneeling and crouching around bike.

 

i dont think that is going to work cause my "dear" country dont support paypal only credit cards. i got some guy that is buying parts in greece or im gonna go to honda dealer and order parts anyway its gonna be a while till next ride.

damn why did not i listened to that stupid chain???!!!

 

I ask because I had a failure but luckily only barely tapped my piston. Haven't noticed and weird sounds or felt anything weird when I.rotate the assembly by hand

 

Quite a few people have had no problems with just valve or head replacements.

I don't recall anyone who has had damage to the pistons etc that actually mattered. (small nicks yes, but not more)

 

Cool!

 

finaly it work again... music to my ears... if anyone need help with replacing valves send me pm.

again thank everybody on this forum for help!

 

Congrats on getting it fixed!

Did you upgrade to manual CCTs? To prevent this ever happening again.

If you have your old ones and want to save money you can convert them for cheap.
https://www.superhawkforum.com/forum...76/#post198209

 

thanks

yes i did. i took old ones in a local workshop and showed them picture of an ape cct a they made exactly the same for 20€ so i don't have to worry about that