Jump to content
CBR1100XX.org Forum

viffer winter project


tomek

Recommended Posts

Well, she started to jump out of 6th gear, there was no point of waiting any longer, the engine had to come out. It was, of course, pita. Way more time consuming vs inline engines. Post mortem exam reviled rounded dogs. Before certain member announces to the world I don't know how to change gears, I'd like to point out I'm second owner, and my XX has 207 k miles on untouched gearbox and clutch. 

2010 vfr1200f does have a history of weak 6th gear issue.

With the engine out I decided to go thru heads ( ports clean up, valves lapping) and degree cams.

Some observations and comparison to XX.

Quality of casting is improved and ports look much nicer.

Valves have better flow improving shape

vallve seats better match ports

Engine has 81mm vs 79 mm for XX bore so the fact intake valves are 1 mm bigger is expected but exhausts are 2mm smaller. Ive seen that kind of scenario on 2015 cbr1000rr engine. Really small exhaust valves and ports.

After 45k miles cam timing was retarded by 3 deg on both banks. Probably courtesy of cam chain getting longer. I just used dremel ( spelling ? ) to cut stock cam sprockets. I took like 5 minutes for both.

Stock piston to head clearance was 1.25 mm, similar to XX, but more then what you see on 1000 superbikes like r1, cbr1000rr. I pulled one layer out of head gasket, .25 mm . That brings squish to 1.0 mm, but ideal figure is 0.75mm for those type of engine. With single piece cylinder block/upper crankcase design there is not much more I can do.

 

Link to comment
Share on other sites

Now, this is one is interesting. There is official recall for driveshafts, the front part goes bad. Of course I was lazy enough to check with dealer whether it was done or not.  Sure enough, it is totally fucked.

Once I put engine back, the bike gets trailered to dealership for recall.

IMG_20191123_113400703.jpg

Edited by tomek
Link to comment
Share on other sites

It takes a lot of hours to do all of that and I have never heard of someone degreeing old cams but it makes sense.  Bike engines have always seemed more intimating than cars.  Can you buy new dogs?  You are so lucky that driveshaft didn't crap out on you on your big Alaskan trip.   BTW-interesting photos.

Link to comment
Share on other sites

Very unusual for 6th to go out, unless you have excessive shift-drum wear, or a fork or shift-shaft is bent.  You could have the trans under-cut while it's out.  That should fix it for good.

I think I would have bought new cam chains, but guessing they are a total pain to replace.

If you can find a shop that can mill a little off the block, you can tighten up that squish area some more.  That's what I did to my drag Bird in 2008, per your advice.  Sure did boost the torque.

Not sure it would be worth it for a touring bike, but figured I'd through it out there.

I wonder if those pistons would fit in a bird motor that had been bored 2mm over?  Pin size the same?  Used ones on Ebay would be cheaper than a piston kit.

Link to comment
Share on other sites

45k. Recall is recall, they gotta do it. It is safety issue. 

You can always buy new dogs, just like cats.😉 

Actually they are integral part of gears, Ive replaced all of them on main shaft, 3rd and 4th ( one part) and 5th and 6th. The way gearbox works dogs of 6th gear engage one from 3/4th gear, so it leaves 5th gear on the main shaft, may as well replace them all. Also there was too much wear for my taste on the middle fork, that is from the pressure from rounded dogs pushing gears a part. New one as well. Plus 6 new crankcase bolts, they gotta be new every time cases ate split. About 300 $ in parts, not too horrible.

Link to comment
Share on other sites

Ive looked into undercutting, was way more $ then new gears.

Block has Honda's nikasil equivalent cylinder bores. Couple years ago I was told by APE you cannot cut the top in scenario like that, the plating could come off.

Another interesting fact, cylinder head gasket has usuall 3 layers, but it is metal, looks like copper and metal sandwich. Never seen one like that.

Edited by tomek
Link to comment
Share on other sites

Didn't realize they had plated cylinders, but understand why that would be a risk.  So, you bought 3 gears (2 being sliders), a fork, and 6 bolts for $300?  That sounds like a bargain to me.

 

Link to comment
Share on other sites

Got curious, and went to look at BB gear prices vs. Busa gear prices.

 

SUZUKI, YOU FUCKING THIEVING BASTARDS!

 

30% more money, for 50% less quality, and 10 times the production volume.  Okay, fine, you make more HP, so 25% less quality.  ass holes.

 

Wish I could drop a Bird trans into my Busa drag bike.  At least it would shift better.

Edited by jon haney
Link to comment
Share on other sites

27 minutes ago, jon haney said:

Didn't realize they had plated cylinders, but understand why that would be a risk.  So, you bought 3 gears (2 being sliders), a fork, and 6 bolts for $300?  That sounds like a bargain to me.

 

yep

Link to comment
Share on other sites

Good thing the trans started acting up and you decided to do the teardown, that driveshaft looks like it was close to grenading which could be real fun at high speed.

 

The work you're doing on the ports & cam timing could wake it up some.  When you reduce the squish the cam timing will retard some, no clue how much as I've never checked, but it would be worth re-checking after you get it assembled.  I understand not machining the cylinder block to gain squish, but why can't the heads be machined?  Seems like it could be safer than taking layers out of the gasket if there's enough material in them.

 

Interesting that you mention the ports/seats on the XX, I was a bit disappointed when I took a XX head apart.  Seems like there's a fair bit of room for improvement which is kinda cool if one wants to put the work into it.

Link to comment
Share on other sites

Cutting heads won't do nothing to squish, you don't understand very basic geometry and/or what is squish. 

Removing 0.25 mm from gasket equals 0.8 deg of crank rotation, it can be calculated if you measure cam sprocket.  Again very basic calculation. 

Anyway, I set timing after reassembly.

 

Thanks for showing up and proving once again you have no clue. 

See you.

Link to comment
Share on other sites

1 hour ago, blackhawkxx said:

He didn't tell you what to do but asked a question.  You could give a basic explanation and help him and others grow in knowledge. 

It would be nice, but unfortunately he can't/won't and must attack/insult.  But, in his defense he is absolutely correct about the squish.  At the time I typed that I was thinking about compression ratio and squish at the same time and convoluted them in my head.  A thinner gasket will increase compression ratio and squish, milling the head will only increase compression ratio.  Basically, squish is the space left in the tightest space between the piston and cylinder head so milling the head won't change that very much if at all, depending on the head and piston shapes.  To effectively increase squish in most engines you have to raise the piston, lower the head, or change the shape of either/both to create a tighter squish area.

Link to comment
Share on other sites

12 hours ago, tomek said:

Thanks for showing up and proving once again you have no clue. 

 

Thanks for showing up and proving once again that you will turn every thread into a shit show instead of just talking about things.

 

Link to comment
Share on other sites

30 minutes ago, SwampNut said:

 

Thanks for showing up and proving once again that you will turn every thread into a shit show instead of just talking about things.

 

Perhaps your bro could just think over things before  posting in my threads. He has exhausted my patience lóoooooong time ago. 

 

Apologies to everyone else.

Link to comment
Share on other sites

I don't think I said anything that could in any way be taken as an insult or challenge, other than the shifting thing which I went out of my way to put a emoticon on to hopefully make it obvious that I was just joking.  I asked an ignorant question that you coulda just answered or ignored, but no.  Since you're unable to act like a decent person maybe you should just go back to ignoring me.  Actually, since you're committed to being a pissy little cunt with nothing worth listening to I'll put you on ignore and make everyone's lives better.

Link to comment
Share on other sites

It's been asked before: when you put someone on ignore their posts aren't shown, but it puts in a little line saying "you've chosen to ignore content by tomek" and then a clickable "options" that lets you see that post, change your ignore settings, or stop ignoring the person.  I chose not to ignore PMs in case he ever gets on the meds or whatever it'll take to be 'normal' and he wants to reach out.

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.

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.

×
×
  • Create New...

Important Information

Terms of Use