Topic: 836 budget and specs

[dustyc]

I'm planning on an 836, which will be my first SOHC rebuild.  I wonder if any of you would let me know what you'd build, why and an idea of the cost so I can figure out what I can afford to build and an idea of performance.

Thanks.

[scondon]

 Try searching "836". Should be quite a few threads to pore through. Be easier to answer specific questions than to write a whole page of general info.

  What model engine will you be rebuilding/

[gkw120649]

Take a look at the Cycle X 850cc big bore kit.  I was thinking about a Weisco 836 but I don't need forged pistons because I won't be racing.  I just need to perk up my motor a little bit.



                                           Cycle X CB750 Big Bore Kits
Cycle X 850cc piston kits are permanent mold , cast pistons.
836cc piston kits are 65mm, our kits are 65.5mm which allows you to re-bore your worn, tired 836cc cylinders.

Cycle X piston kits feature:

* Pistons, rings, wrist pins, circlips.
* 10 1/2 compression ratio.
* Large valve relieves for hot street cams.
* Replacement rings are in stock.
* Balanced exact and weigh the same as stock 750 pistons.
* Head gasket now included with kit
 Note: Extra displacement and compression require longer duration cams for best performance and reliability.
 
                                                            $ 249.00                EN-1010

Greg in Chicago.

[dustyc]

Sean, I thought a new discussion would be warranted since prices go up, supplies dry up, new products get developed and suppliers come and go.  I was hoping to get a brief review and budget breakdown all in one spot rather than spread over alot of posts.  And if there are any newer builders that haven't already posted about theirs, give a space to mention what they've done.  Hopefully it will benefit others looking at doing a big bore. 

I've done some searching already.

[seaweb11]

This was my tally 1 year ago.  It has gone up since then considerably

Cost:
Bike $1300
Freight $359.85
2 motors $350.00
carbs $300.00
Frame Straightening $500.00
Frame Mod kit $132.00
Frame Mod kit cut/weld/install $400.00
Engine Paint/polishing supplies $100.00
Aluminum case welding $100.00
Tapered bearings $50.00?
Brand New wiring harness $150.00
Cyl Bore & sand blasting $350?
        (Cycle exchange)
Lightened fly wheel $65.95
Oil Seal Kit $39.00
836 Head Gasket $49.00
836 Pistons $499.00
Barnett clutch $79.00
Heavy duty Clutch springs $14.00
Heavy Duty Cyl studs $84.00
Complete Gasket set $79.00
Primary Chains $119.00

Megacycle Cam $244.95

Engine Build:
8 -  4 hour 2 way c/w ferry drive trips to buildres shop @ $6.00 per gallon?
Labour to tear apart 2 really FCKED UP engines and make this one with all the parts I provided along with a few the builder parts provided $1911.55.

Building a bike priceless....................
$7275.35  So far and it just sits on two tables?

[scondon]

Sean, I thought a new discussion would be warranted since prices go up, supplies dry up, new products get developed and suppliers come and go.  I was hoping to get a brief review and budget breakdown all in one spot rather than spread over alot of posts.  And if there are any newer builders that haven't already posted about theirs, give a space to mention what they've done.  Hopefully it will benefit others looking at doing a big bore. 

I've done some searching already.

 Gotcha dusty, sounds good   Our "search" function IS a disaster

  Going on my 4th and 5th overbore build and the cost vs. power vs. time vs. availability vs. favorite vendor vs. "what the guy at work told me", etc... gets my head spinning. I can no longer give a simple answer.

  Next engine is:

  850cc Cycle-X pistons w/ cylinder bore-

  $475 + shipping

   head: Dynoman valves/Kibblewhite springs and guides/titanium retainers/Mrieck port and chamber work/ minor machine work-

$1350 + shipping

Ape crank

$225? + shipping

Falicon or Carillo rods

$1000-$1400 + shipping

Megacycle grind cam

$360 + shipping

HD studs
 
$80 + shipping

Crankcase studs

?

Gaskets/o-rings/bearings and various other OEM supplies that will become apparent once the engine comes apart

$350-$750

  Money that engine builder will receive for putting this together

$0.00

Tools?

supplies?

Therapy?

 

[SD750F]

And I have been trying to buy a couple parts from Cycle X all day. No answer or call back later and talk to Sue...

[scondon]

And I have been trying to buy a couple parts from Cycle X all day. No answer or call back later and talk to Sue...

  It's a two person family shop, I think. Ken does the bike work, Sue does the billing/shipping. Can take a few calls sometimes but the service is pretty fast once order is placed.

[754]

Dusty, can you give us a bit more info?

 First do you have , cam, headers ignition??

 2nd do you want to spend under 1500?

or up to 3500.?? or more..

 You can put just an 836 only, in for price of kit + gaskets.. plus 100-200 for boring, add more if things are not flat.. and can you assemble yourself..

 in short outline your  basic plan..

[dustyc]

Well, I'm not sure.  I'm not sure what they're capable of at different levels.  I don't have extremely deep pockets at the moment, but I don't want to short change the effort.  I'd rather take it slow than skimp

I'd like to make it a sleeper, either in a '74 frame or '76.  Not noticeably hot rodded, but able to screw with my Ducati riding friends as much as possible -again, I'm not sure what a big bore SOHC is capable of.

Once the cat is out of the bag with those guys, I'd move it into another frame.  Leaning more toward a CR look than a cafe really, CR style tank, solo seat with cowl,  Goldwing/750A aluminum spoked wheels, -which leads me to another question, are there any 18" DID aluminum 40 spoke rear wheels that will mate with a rear hub?

What I've got is an old drag bike's 836? -as yet unmeasured and unchecked other than it turned over.  BigJim's got it and is going to show me the way through rebuilding it.  I don't know if the rods are stock, or what condition any of it is in really.  I'm almost planning for the worst case scenario of having to go from scratch.  If there's something massively wrong with it, I've got a few other 750 engines I could work with.

I'd like to hear what I could expect from just an 836 piston kit, cam and some porting work, up to different carbs, lots of porting, heavy duty everything and all the bells and whistles.

[MCRider]

Well, I'm not sure.  I'm not sure what they're capable of at different levels.  I don't have extremely deep pockets at the moment, but I don't want to short change the effort.  I'd rather take it slow than skimp

I'd like to make it a sleeper, either in a '74 frame or '76.  Not noticeably hot rodded, but able to screw with my Ducati riding friends as much as possible -again, I'm not sure what a big bore SOHC is capable of.

Once the cat is out of the bag with those guys, I'd move it into another frame.  Leaning more toward a CR look than a cafe really, CR style tank, solo seat with cowl,  Goldwing/750A aluminum spoked wheels, -which leads me to another question, are there any 18" DID aluminum 40 spoke rear wheels that will mate with a rear hub?

What I've got is an old drag bike's 836? -as yet unmeasured and unchecked other than it turned over.  BigJim's got it and is going to show me the way through rebuilding it.  I don't know if the rods are stock, or what condition any of it is in really.  I'm almost planning for the worst case scenario of having to go from scratch.  If there's something massively wrong with it, I've got a few other 750 engines I could work with.

I'd like to hear what I could expect from just an 836 piston kit, cam and some porting work, up to different carbs, lots of porting, heavy duty everything and all the bells and whistles.

An 836 w/cam and porting is very fun, if not formidable in the right hands. Against a duck you have a serious weight disadvantage. Build it for torque, not high RPMs. With proper gearing for your terrain you could surprise them, maybe not beat them. Depends on the rider.

Figuring a CR750 was good for 90HP, an 836 built by mere mortals with all the bells and whistles should approach that.

My 888cc had, and will have again all the bells and whistles short of the lightweight knife edge rods. Hope to get it on a Dyno someday.

[eurban]

Figuring a CR750 was good for 90HP, an 836 built by mere mortals with all the bells and whistles should approach that.

If you want close to 90 rear wheel HP from an 836, you wont be building the engine for torque!  You will need to build a high RPM screamer and I promise that it will cost big $$ and that it won't be particularly torquey any more.  I would guestimate that 70 rwhp is more like it from a moderate 836 build with good low end grunt . . .

[lordmoonpie]

I'm after 100bhp....it's all sat on the bench and so far I'm into it for over $36,000! No it's not a typo 

[dustyc]

I guarantee I won't be spending that kind of money.  What have you done that you have that much in it?

[MCRider]

Figuring a CR750 was good for 90HP, an 836 built by mere mortals with all the bells and whistles should approach that.

If you want close to 90 rear wheel HP from an 836, you wont be building the engine for torque!  You will need to build a high RPM screamer and I promise that it will cost big $$ and that it won't be particularly torquey any more.  I would guestimate that 70 rwhp is more like it from a moderate 836 build with good low end grunt . . .

Be kind, you're shooting down an old man's dream!   

here's an interesting link: http://www.satanicmechanic.org/dyno.shtml

There's an 836cc there with stock pipes and about 70RWHp. No mention of carbs either.

Until someone puts it on a Dyno we are all just bench racing.

And the biggest factor in real world horsepower is the guy turning the throttle. I think $1,000 in track training may be better spent than $1,000 in a motor.

[andy750]

The only CB750 Ive seen (and rode) that put out 93bhp (or was it 97?) and has the Dyno readings to prove it, is the Million Dollar CB owned by Mike Rieck. And this bike is amazing, as is the work thats gone into it.

But then Im waiting for lordmoonpies "Billion Dollar CB" to get finished 

cheers
Andy

[MCRider]

The only CB750 Ive seen (and rode) that put out 93bhp (or was it 97?) and has the Dyno readings to prove it, is the Million Dollar CB owned by Mike Rieck. And this bike is amazing, as is the work thats gone into it.

But then Im waiting for lordmoonpies "Billion Dollar CB" to get finished 

cheers
Andy

That sounds great! What displacement?

On the Dyno list I posted the second one from the bottom has an interesting torque and hp combo graph.

Heck I have fun on my wife's 25hp Burgman!

[lordmoonpie]

I have to say Mike Rieck and Mark McGrew have been my inspiration on this project. With a DOHC crank and longer rods my displacement is probably close (I haven't worked it out yet!) to 750cc but the only original bits are the cases....it'll be one of three things:

1. a monster motor
2. a money pit of a lemon
3. a big fireworks party

But hey - I've had four years of development to get through and learn and that alone has been a hugely worthwhile exercise.

Search on "Ultimate Motor" for the pics

Once finished I'm going to try and emulate a hero of mine - John Britten and build a home made V-twin from scratch....mad? Yes probably but it's the most fun you can have with your pants on! 

[lordmoonpie]

Man I just have to say - this forum is the absolute best! The dogs danglies as we might say here in Blighty! I have learnt so much from just being here on the ride....God bless ya!

[MRieck]

I'm after 100bhp....it's all sat on the bench and so far I'm into it for over $36,000! No it's not a typo 

You'll get that LMP.

[MRieck]

The only CB750 Ive seen (and rode) that put out 93bhp (or was it 97?) and has the Dyno readings to prove it, is the Million Dollar CB owned by Mike Rieck. And this bike is amazing, as is the work thats gone into it.

But then Im waiting for lordmoonpies "Billion Dollar CB" to get finished 

cheers
Andy

98HP with 915cc Andy.

[MCRider]

The only CB750 Ive seen (and rode) that put out 93bhp (or was it 97?) and has the Dyno readings to prove it, is the Million Dollar CB owned by Mike Rieck. And this bike is amazing, as is the work thats gone into it.

But then Im waiting for lordmoonpies "Billion Dollar CB" to get finished 

cheers
Andy

98HP with 915cc Andy.

If I may say...that's really kewl! 

[andy750]

The only CB750 Ive seen (and rode) that put out 93bhp (or was it 97?) and has the Dyno readings to prove it, is the Million Dollar CB owned by Mike Rieck. And this bike is amazing, as is the work thats gone into it.

But then Im waiting for lordmoonpies "Billion Dollar CB" to get finished 

cheers
Andy

98HP with 915cc Andy.

Thanks Mike - committed to memory! Hope to see you Sunday and if not, then I may have to drop by next week for some Chimay talk 

Cheers
Andy

[andy750]

Search on "Ultimate Motor" for the pics

Once finished I'm going to try and emulate a hero of mine - John Britten and build a home made V-twin from scratch....mad? Yes probably but it's the most fun you can have with your pants on! 

I saw the Britten bike at Barbers Museum, Alabama and I have to say its really amazing! Im expecting great things from you LMP!!!

good luck
Andy

[lordmoonpie]

Ha ha - well I'll see how close I get to Mike's 98bhp - that's some target to aim for. If mine falls flat and I get like 68 bhp, maybe I won't try for the Britten type twin just yet.....but, that's the plan