Bonneville America Forums Forums Technical Forums Performance Mods GOT MY HEAD BACK!!!!!!!!!!!!!!!!!!

well my head came in today from florida. all i can say is wow it looks sexy. i will take some pictures of it tomorrow and post them up. i can feel the power gain just by looking at them . will have the motor back together saturday and maybe if the weather keeps up i may be able to drive it home from my friends

Frank

You know what they say,
"You'd lose your head if it wasn't bolted..."
Oh, you meant the bike.
Never mind.

Frank, who did the work? I'm sure you posted that earlier, but my short term memory is shot.

bill gatley at bonneville performance did his thing. oversized valves and a full port, polish, and flow on a cnc machine and flow bench

Frank

HOW MUCH DID IT COST YOU?......ANGELIS

I would like to get this done as well, I am thinking of this mod in conjunction with the Thunderbike cams, or should I use the stage 1 cams Bikerthug just used on his?

not sure about cams, price is listed on the bonnevilleperformance site. hurts me to much to say it out loud lol. also i now have a double valve spring. forgot to add that part. here are some pics of the work http://community.webshots.com/album/561394035xNKDvy

Frank

Nice shots. My fav is the two jugs next to eachother, before and after.

I hope Yota doesn't read that...

Very nice work, here's a price list of what I got quoted in the UK for my head work.

Here is the price and it sounds really good, but I just cannot afford to do this.

4 x Nucleus Hi-flow Lightweight inlet valves £120.00
4 x “ “ “ Dome Exhaust valves £120.00

8 x Nucleus race guides £160.00
8 x fit and diamond hone guides to match stems £078.00

4 x Existing exhaust seats reprofile 3 angle £060.00
4 x Hardened inlet seats fit, Blend to chamber o/d to suit oversize valve £180.00
4 x Inlet seats profile 5 angle to suit valves £040.00

Flow ports to suit valves, carbs and manifolds £260.00
Modify combustion chambers £040.00

Then underneath he has written:-

If you want exact replica of 100 + BHP job this involves welding the inlet ports and S wirlflow on inlets £190.00

Apparently he has already done this on a Bonneville and has dynoed of over 100 BHP at the rear wheel, sounds a little frightening to me but if you have the money this is the place to get your work done in the UK..

Cylinder Head Shop

i went will bill gatley because he races these bikes and has done TONS of R&D. to get 100hp you need to do with the 11 or 1200 kits, or have a ton of comression. i believe with the setup i will have it should put me around 80-80hp and 60-65IBS

Frank

Hi Frank

Len from the Cylinder head shop says he has done this on a Bonneville with the 904 BB kit from Wiseco and got the magic 100 bhp. I would love to do it, just to see the difference but cannot justify the amount of cash he is talking about, remember the bonneville is 360, you have 80bhp from a 270 which is really good anyway..

not trying to argue but to be honest i dont think its possible to get 100 hp out of a 904 unless they make the dyno say it or he has a LOT of compression.

Frank

if you want to get more expert info on this check out the delphi forum, its a much different type of forum but the guys know there stuff

Frank

I wouldn't know, never tinkered around like that before. Yea i messed with cars in my younger days, but that was just to keep them on the road, never been bothered about going fast and these days my brain is a little slow hence why I ride the America and not a pocket rocket..

Cheers Frank

naturally aspirated? and only 904 no. but i think the 11 and 1200 kits with headwork and cams can with matching TQ. but thats not what this thread is really about so i will just stop now and go back to being thrilled i can finally put my motor back together

Frank

Hurry up Frank, there's a whole group of 904 wannabes waiting for your ride report!

saturday is the day and i think i can actually ride it home. been melting and no snow in the forecast so i think i am good. then it goes away till spring . but i will def post a report

Frank

Well?

well its going to have to wait. the bores and different sizes. one is to small and needs to be inlarged so that will be done and then i can put it back together. note to self: make sure the shop you use knows EXACTLY what they are doing

Frank

Dude that stinks! Keep me posted bro. Wish I knew a good shop!!

That's a real bummer Frank. Hope it sorts out soon for you mate.

thanks. i know it will work out one way or another. lesson learned, make sure you go with people who have done this before on THESE bikes

Frank

Sorry to hear your having problems Frank, hopefully get it sorted then let us know how that "BEAST" feels

If you put it back together as was would that make it an 850? And then what about the challenge for jetting and then theres the torque effect on one side, petrol consumption etc etc what a project!!
Being sensible for a minute what a let down and make sure they hone the bores out (do they have to do that with the pressed in sleeves ?) hope every thing goes well for you now

Blessings

Revnd, the answer to your question is yes, you still have to hone pressed sleves.....Angelis

and the bike will be a 904, i wont touch jetting for now and will dyno it when broken in. i am sure my mpg will be just about the same also unless i am hard on it

Frank

update young man?

we are wwwaiting!

LOL

waiting on the machine shop to get there heads out of there butts and fix there mistake

Frank