Building a race bike.

Posted: Fri May 30, 2014 11:45 pm

Also, Mile High Cranks out of Denver does some pretty nice custom work like you are looking for.

Posted: Sat May 31, 2014 12:51 am

Hey JJam,
I have a set of 1000c sleeves setting on a shelf that I will gladly donate to the cause.
Send me your address if interested.

Don,

Posted: Sat May 31, 2014 1:35 am

I talked to 3 places in the PDX area and one was interested and explained a lot to me in 40min. But in the end they are more set up for just regrinds.
I told him that I really didn't have many options for bearings off the shelf and that was kind of a deal breaker. He just barely had a wheel as narrow as the journal.
He said to try Falcon out of Florida?
The other two weren't interested as soon as I said motorcycle. Too small they said.

I will keep looking and in the mean time tear into this 1000c and start prepping a set of cases.

Also does anybody know where to get custom bearings maybe even with shoulders on the sides????

I ask because I measured my VF rods today and they are just over 15mm ctr to ctr but this was just a close measurement. That was nice.
They also have 18mm pins which is nicer BUT they are a few mm narrower then the CB rods on the big end. I'm assuming that shouldered bearings
would be needed.
You machinist guys or anybody got any input on this? Pros/cons?

Thanks for all the input guys!! Cool

Jim

Posted: Sat May 31, 2014 4:14 am

Maybe that's Falicon in Clearwater, Fl? They do legendary crank work for bikes. I bought my ARP bolt stretch gauge from them, and some rods years ago.

http://www.faliconcranks.com/

Posted: Sat May 31, 2014 4:17 am

JJam wrote:

The other two weren't interested as soon as I said motorcycle. Too small they said.

Jim

What do you expect in Portland? They're used to doing Freightliners. Wink

Red CB1100F Joined: Jul 19, 2010 Posts: 6420 Location: Ct

Jim, yer gonna have to post some pics soon to keep simpletons like me interested!!!! Pics of anything for petes sake.

Too much reading. Cool

CB1100F Joined: Jun 18, 2006 Posts: 2528 Location: UK

Hi Jim

Damage mentions in this thread about using GS750 Rods in his Engine

Link to GS750 Rods

Keith

Posted: Sat May 31, 2014 5:13 am

ctluba wrote:

Jim, yer gonna have to post some pics soon to keep simpletons like me interested!!!! Pics of anything for petes sake.

Too much reading. Cool

LMAO Steve!!

This is one of the hardest parts of any build. Figuring out the game plan before you start. Makes it go smoother in the end and cost less.

OK, I will show pics of my unfinished frame but most have been seen in an old thread of mine. My first one to be exact.
Here's a link to that thread until I take some new up to date pics of the frame later this weekend. This thread shows the laid down shocks that I did to the frame. Not my best work but I was pretty green at welding at that point. Plus I didn't have as many tools and my shop was a 9x18 ft garage. It was tight in there.

Link
http://www.cb1100f.net/modules.php?name=Forums&file=viewtopic&t=54327&highlight=crs+carbs+sure+nice

I'm leaning towards going full out and building the 70mm motor and the 60mm crank with custom pistons and rods. This is a bike that could help my rep and be a very good advertisement. "OR" it could slap me in the face if I don't do it right? It's really out of my means but every successful bike builder that I know of has at least one really BAD ASS bike. Or there just messing around IMO. Am I wrong???
Pretty much a hail Mary IMO and I'm in for the WIN.

Keep it twisted, Jim

Peace, Jim

Posted: Sat May 31, 2014 11:26 am

JJam wrote:

Also does anybody know where to get custom bearings maybe even with shoulders on the sides????

I ask because I measured my VF rods today and they are just over 15mm ctr to ctr but this was just a close measurement. That was nice.
They also have 18mm pins which is nicer BUT they are a few mm narrower then the CB rods on the big end. I'm assuming that shouldered bearings
would be needed.
You machinist guys or anybody got any input on this? Pros/cons?

Thanks for all the input guys!! Cool

Jim

If the BE of the rod is too narrow but the bearing was good on the diameter you could have your pistons made and the rods could be piston guided. You would have to tell them this when you are designing the piston.

Posted: Sat May 31, 2014 11:53 am

Well guy's it never ceases to amaze me just how friendly everyone is on here! i'm stuck in my TV shop on an unbelievably quiet Saturday afternoon and this thread has just made the last 90 minutes pass in a flash!

Bookmarked!

Oh! Well I suppose i.d better put that 55" curved OLED LG TV out on display now....

Posted: Sat May 31, 2014 3:42 pm

I sent Dave at Mile High Cranks an email to see what it might cost to weld and grind a 750 crank. I'll let you know when I get a reply.

Also, I second Nathan's suggestion regarding pin guided rods.

Regarding the VF rods- are the rod journal sizes the same for the CB and the VF? If the VF journal is smaller than the CB then the crank might not need to be reground. Also how much power/RPM can those VF rods handle? Anyone know? To paraphrase Brent, you don't want to skimp on the bottom end.

Nich

Posted: Sat May 31, 2014 3:45 pm

Captain wrote:

I've started to really think about this and the following is my suggestion about how to do this and get the maximum bang for your buck.

Go 70 mm bore and 60 mm stroke and use the RSC/AHM barrel as it is. De-stroke a 750 crank to 60 mm by sending it to APE (No idea what that will cost but its achievable as it is only a 2 mm reduction) resulting engine size 924cc. Lighten the crank yourself along the lines I have explained. Chose the best quality and longest rod you can using 17 mm wrist pin and have a custom piston made to suit the combination. The advantage here is that at 70 mm bore you don't have to re-sleeve the barrels, have better breathing, you can access rings from Total Seal in that size and as the cost to produce the piston is no different being either 69 or 70 mm.
If this was my project this is what I would be doing.................

Captain

Ok I just read this part again. It didn't down on me that with the shorter stroke I could maybe use 1100 rods which will save me a good chunk of change.

Am I correct that 1100rods are approximately 117+/- a few? I can measure them accurately but just trying to get this all in my head.

Brent hasn't posted back so I am assuming that he is on the way or already in Italy checking on the heads.
I will admit that I am kind of a rookie at hoping up these motors to this extreme. Modern MX bikes that I'm use to never need this much work to be competitive.

Anyway off to the machinists shop to see about lightening the buckets in an EDM sinker machine. It burns its way to make holes but since the part is submerged in a fluid while it happens. The bucket has no ill effect doing it this way.

Thanks for all the ideas and help guys!! Cool

Posted: Sat May 31, 2014 3:52 pm

BTW anybody have a set of donut 750 or 900 cases that I could buy? I have none. I would prefer 750 with the solid mounts but if not I can just plug them which is easy enough.

Thanks Jim

Posted: Sat May 31, 2014 4:10 pm

Jim, that motor will sound angry as hell! Kinda like a CR930.

CB1100F Joined: Jun 18, 2006 Posts: 2528 Location: UK

Jim
A 1100 rod is close to 117.5 just measured with a vernier,and a Spark Eroder (EDM) will will do the buckets ok, used one alot when i worked in engineering, Could take a while to do 16 of them.

Posted: Sat May 31, 2014 10:02 pm

I looked at de stroking a 900 and using 1100 rods to make a displacement class. The difference in length between 900/1100 and 750 rods is about 4.5mm, from memory.

You de stroke the difference and use 1100 rods any difference is made up with gaskets.

Do you think this is a good rod for the new rpm range? Piston speed should be down from stock as well as piston weight both a plus.

Does anyone have a TL bucket and shim, GSXR retainer, to compare for weight?

Jim

Posted: Sun Jun 01, 2014 1:55 am

jkotsi wrote:

Do you think this is a good rod for the new rpm range? Piston speed should be down from stock as well as piston weight both a plus.

Piston speed will only drop if the rpm stays the same as stock. With Brent's head, etc. this engine should easily turn more rpm bringing piston speed back up. The question is how much more rpm?

Hawk Joined: Dec 16, 2007 Posts: 371 Location: warwick,uk

jkotsi wrote:

I looked at de stroking a 900 and using 1100 rods to make a displacement class. The difference in length between 900/1100 and 750 rods is about 4.5mm, from memory.

You de stroke the difference and use 1100 rods any difference is made up with gaskets.

Do you think this is a good rod for the new rpm range? Piston speed should be down from stock as well as piston weight both a plus.

Does anyone have a TL bucket and shim, GSXR retainer, to compare for weight?

I have tl buckets and shims . Will measure as best I can

Jim

Posted: Sun Jun 01, 2014 12:23 pm

You are right Nich, rpm should go up.

De-stroking from 69 to 60mm changes the rod ratio from 1.70 to 1.96, with a piston speed limit of 4500ft/min the max rpm goes from approx. 10,000 to 11,500. Would the Wiseco pistons work well in this range?

So the working rpm range would be to 11,000 with the new head design giving a better fill, more efficient work.

A hard budget helps you evaluate best mods, best performance return for the dollar. Lightening the buckets with aluminium retainers and a smaller 7mm shim may be enough to operate with an 11500 limit, spend the difference on piston coating or better bearings, my opinion.

But don't stop, I love what you are doing.

Jim

Posted: Sun Jun 01, 2014 4:22 pm

nathanhouse wrote:

JJam wrote:

Also does anybody know where to get custom bearings maybe even with shoulders on the sides????

I ask because I measured my VF rods today and they are just over 15mm ctr to ctr but this was just a close measurement. That was nice.
They also have 18mm pins which is nicer BUT they are a few mm narrower then the CB rods on the big end. I'm assuming that shouldered bearings
would be needed.
You machinist guys or anybody got any input on this? Pros/cons?

Thanks for all the input guys!! Cool

Jim

If the BE of the rod is too narrow but the bearing was good on the diameter you could have your pistons made and the rods could be piston guided. You would have to tell them this when you are designing the piston.

???? Nathan I never knew of such a set up. That could work is there any cons to this set up?

Posted: Sun Jun 01, 2014 5:07 pm

F-crazy wrote:

I sent Dave at Mile High Cranks an email to see what it might cost to weld and grind a 750 crank. I'll let you know when I get a reply.

Also, I second Nathan's suggestion regarding pin guided rods.

Regarding the VF rods- are the rod journal sizes the same for the CB and the VF? If the VF journal is smaller than the CB then the crank might not need to be reground. Also how much power/RPM can those VF rods handle? Anyone know? To paraphrase Brent, you don't want to skimp on the bottom end.

Nich

Thanks Nich for the info and help with locating a crank specialist.

I'm not sure on the VF rods for MAX RPM's.

The more and more that I think about it the more custom rods sound like the way to go.

The other thing that is bothering me is if I should lighten the crank all the way to Brents specs? The 750 crank is already lighter then the 900 crank and they are almost half as wide of halves. He hasn't tested this crank and not sure that I want to be the first with an expensive motor?
Maybe just lighten it by knife edging would be the safe bet?
I will get the actual specs asap.

So much to think about. Confused

Posted: Sun Jun 01, 2014 5:11 pm

One step at a time Jim. Plenty of time my friend. This thread is AWESOME! So much knowledge from you guys...............

Posted: Sun Jun 01, 2014 5:13 pm

krgood0 wrote:

Jim
A 1100 rod is close to 117.5 just measured with a vernier,and a Spark Eroder (EDM) will will do the buckets ok, used one alot when i worked in engineering, Could take a while to do 16 of them.

My machinist buddy and I cam up with a jig design (that I have to built) and it will hold 6 and maybe 8 buckets at a time. It will be indexable and burn two holes in the buckets all in one pass so it won't take too much time. I plan to offer this service in the future, so I want to build the jig correctly.

Posted: Sun Jun 01, 2014 5:37 pm

JJam wrote:

nathanhouse wrote:

JJam wrote:

Also does anybody know where to get custom bearings maybe even with shoulders on the sides????

I ask because I measured my VF rods today and they are just over 15mm ctr to ctr but this was just a close measurement. That was nice.
They also have 18mm pins which is nicer BUT they are a few mm narrower then the CB rods on the big end. I'm assuming that shouldered bearings
would be needed.
You machinist guys or anybody got any input on this? Pros/cons?

Thanks for all the input guys!! Cool

Jim

If the BE of the rod is too narrow but the bearing was good on the diameter you could have your pistons made and the rods could be piston guided. You would have to tell them this when you are designing the piston.

???? Nathan I never knew of such a set up. That could work is there any cons to this set up?

Sure, instead of the crank journal width and the rod BE journal with deciding where the journal rides lateraly the pin end within the piston does. So you would need to have a very accurate measurement of your small end rod width so your piston manufacturer could make the pistons accordingly. Or, if you have pistons already you could make precise "washers" that go between the rod SE and the piston pin tower. I don't think this is as nice a way to go but it works. I've pulled apart Hendrick Cup engines that were done this way. I can't remember if we used a 630 bronze alloy for the spacer or something else. I've also seen the washers get chewed up and wreck an engine, not bc of the spacer but bc of other factors that led to the spacers failing. You would also have to find out the correct amount of clearance for them bc it might be different from the BE size clearance spec. One slight down side might be that it would be slightly more weight on you reciprocating end. I feel the only real reason why YOU would want to do this is if you had a good rod that met all you other needs well but is just more narrow than stock. Anyway, put the idea in your back pocket, you never know when stuff like this may come in handy!

Posted: Sun Jun 01, 2014 5:47 pm

jkotsi wrote:

You are right Nich, rpm should go up.

De-stroking from 69 to 60mm changes the rod ratio from 1.70 to 1.96, with a piston speed limit of 4500ft/min the max rpm goes from approx. 10,000 to 11,500. Would the Wiseco pistons work well in this range?

So the working rpm range would be to 11,000 with the new head design giving a better fill, more efficient work.

A hard budget helps you evaluate best mods, best performance return for the dollar. Lightening the buckets with aluminium retainers and a smaller 7mm shim may be enough to operate with an 11500 limit, spend the difference on piston coating or better bearings, my opinion.

But don't stop, I love what you are doing.

Jim

Huh??? I was thinking of the 750 crank as the donor but if a 900 crank can be de-stroked that far (just more welding) that sounds like a stronger option and Brent has already explained to me how to do it and he has tested out his set up. I'm much happier with that Idea since both need to be de-stroked anyway.

Posted: Sun Jun 01, 2014 5:51 pm

Thank You Nathan for your knowledge!

Posted: Sun Jun 01, 2014 6:33 pm

Sorry Jim, I screwed that up, you are running with Brent's 750 cylinder then the total de stroke is 62mm reduced to 60mm, 2mm. The rod ratio is still 1.88

Jay from APE thought the max journal offset would be 3.5mm, so 2 is good

Before you decide on a crank weight ask Dennis if he has a preference, ride style might need to adapt to a really rev happy engine.

Looks like Yosh dropped 15 grams off a 45g bucket and 6g off the stock 10g shim. KZ650 shims drop 4g. No mention on the retainer mod.

Posted: Sun Jun 01, 2014 7:01 pm

So much to think about.
OK, so if 3.5mm is the furthest that APE thinks is doable, then I need to stick to the 750 crank. There's another option to cross off the list. At least we're getting somewhere.

I need to cool my jets and just add up all the options before this thread goes to much further.

Ounce Brent gets the cost of the head figured out I will proceed at that point with the rest of the parts.

In the mean time the frame needs a lot of work so I will focus on that.

Thanks again guys, Jim

Posted: Sun Jun 01, 2014 8:21 pm

OK, Just for Steve

here is some up to date pic's of the unfinished frame. I wanted to wait until I get the frame jig made and the rest of the braces in but
in my normal fashion I'll let you watch as it transforms.

In these picture's you can see the rear of the new upper shock locations and the X brace.
If I were to do the shock mounts again. It would be a lot nicer and lighter. This took me forever to build in like 09 and I was Green as hell with my fabing skills.
Wish I had never did this until now. Oh well. I learned a lot.

The steering stem will get moved back 1" and 1degree steeper angle.
Until I have the jig made up and 100% square. I won't do a thing to this part of the build.

Swiss cheesed some of the frame pieces.

Still needs some welding but the kickstand mount is cast iron and weighed 1.5lb. The new tube is 6oz. so that helped.
I did this with a set of solid mount 750 cases bolted into the frame Before I cut it apart.

I will copy the AHM bikes and drill the frame in front of the swingarm pivot bolt. Then weld on a nut which will hold a 6mm bolt.
The bolt will push the axle to the back and not let the bolt move around which helps keep the bike stable.
You don't have to but I will machine flats on the pivot bolt for the pinch bolts to land square on.

This section of the frame will be boxed in for more strength. Same as DonR's bike and what I did on Motonicks single shock bike.

Originally I had made and sell these (this was the 1st one so the new ones are nicer) male female pinch connectors for the 750 frame split.
Thus helps keep the bike stable.
I will now be grinding this off and welding the frame solid and will save some more weight.

That's all I have for now.

Posted: Mon Jun 02, 2014 12:49 am

Bought a set of solid mount 82 750 cases that are Donut style with the added webbing for strength. Cool

$90.00 shipped to me was a decent deal IMO.

Also found a set of 320mm floating discs and some other goodies today in my parts pile.

Working on a set of 72mm Aris pistons for it as well.

Have a great week, Jim