Author Topic: No Reserve Racing - Project and status updates  (Read 29912 times)

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Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #25 on: May 09, 2015, 09:48:04 PM »
And now for the third set-back ;)

Nothing major on this one, but it did kill some time.  I ordered the solid transmission locator pins from the CB175,  instead of the hollow pins used on the CB160.  But it turns out the CB175 pins are a little taller than the cb160 pins (I know, I should have caught this earlier).

For those of you new to the CB160 (like me), the transmission has bronze bushings at the end of each shaft, which are held in place by a hollow locator pin.  This pin can deform/bend under load (as one of my original ones was) and cause shifting problems.  Upgrading to solid ones should help. 

Anyway, quick fix with the rotary tool:
« Last Edit: May 09, 2015, 09:49:44 PM by Kickstart »
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #26 on: May 09, 2015, 10:00:32 PM »
Here are some pictures of the case rebuild, and installing new pistons:
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #27 on: May 09, 2015, 10:04:45 PM »
Our biggest time kill today (yesterday) was the starter block-off plug.

You can see it to the left in the attached picture.

It seemed to be just a tad larger than the starter gear mechanism that was in there and we had a lot of trouble getting the case halves to fit back together.  We probably spent over an hour test fitting the plug multiple times and comparing it with the original part.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #28 on: May 09, 2015, 10:07:49 PM »
Hopefully everyone can access this link:

My friend set up his camera to take a time-lapse video of our assembly work today... kind of funny:
https://drive.google.com/file/d/0B_6cwdWhxpG9WVB1bDlIbEZjYms/view?pli=1
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #29 on: May 09, 2015, 10:12:54 PM »
Here's a picture of me digging back through the trash after realizing I threw away one of the oil seals that came the new set I bought.

... and then once I recovered the new seal from the trash, I mixed up which one was which and couldn't figure out which was the old one, and which one was the new one.  :)  Surprisingly, they both looked to be in the same shape. 

We never figured out with certainty which one was the new one. Just had to go with our best guess.
« Last Edit: May 09, 2015, 10:26:09 PM by Kickstart »
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #30 on: May 09, 2015, 10:21:31 PM »
So we ended today (yesterday now) with a bad break.

We were about to install the head, and starting putting the cam chain tensioner into the head when we realized the threads in the head for the tensioner lock bolt were stripped.

It's really not a great design.  It's a tiny bolt used to hold the tensioner in place (which doesn't seem to have a tapered rod like on the CB750)... so I suspect this is probably a common problem back in the day with people over torquing this bolt.

You can tell in the attached picture that the bolt is bent.  So some previous owner probably cranked on this bolt too much and inadvertently stripped the threads in the head.

Also attached a picture of the little hole in the head the bolt goes into (head upside down in the picture). 

I really, really, don't care for this design.  I'm not even sure how that O-ring sealed properly.

Anyway, this pretty much ended the build for the day.  We have to figure out how best to resolve this problem - hopefully this won't push back our schedule too much.

« Last Edit: May 09, 2015, 10:24:02 PM by Kickstart »
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Online HondaMan

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Re: Le Mans start CB160 by mid-June or bust
« Reply #31 on: May 09, 2015, 10:52:05 PM »
So we ended today (yesterday now) with a bad break.

We were about to install the head, and starting putting the cam chain tensioner into the head when we realized the threads in the head for the tensioner lock bolt were stripped.

It's really not a great design.  It's a tiny bolt used to hold the tensioner in place (which doesn't seem to have a tapered rod like on the CB750)... so I suspect this is probably a common problem back in the day with people over torquing this bolt.

You can tell in the attached picture that the bolt is bent.  So some previous owner probably cranked on this bolt too much and inadvertently stripped the threads in the head.

Also attached a picture of the little hole in the head the bolt goes into (head upside down in the picture). 

I really, really, don't care for this design.  I'm not even sure how that O-ring sealed properly.

Anyway, this pretty much ended the build for the day.  We have to figure out how best to resolve this problem - hopefully this won't push back our schedule too much.


Yep...when the cam chain got noisy from a too-hard tensioner slider, owners would try to [over] tighten the cam chain, damaging this thread in the process. There are (were) a bunch of them out there, from Spring Honda in Elmhurst, IL, circa 1969-70, with larger bolts in those holes.

It's a quirk of the design that oil just happens to not splash against this bolt, which probably has a lot to do both with them stripping and the O-ring sealing so well?

It seems to me, you're making GREAT progress!
:)
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline vfourfreak

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Re: Le Mans start CB160 by mid-June or bust
« Reply #32 on: May 10, 2015, 02:41:19 AM »
This is a fun project, and I am very envious. CB160s are rarer than a very rare thing over here, no chance to find one except for crazy money.

I have a repro of the CR93 parts list if it would help with getting the frame etc ready for racing ?? Let me know if you want anything scanned.

Kev

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #33 on: June 08, 2015, 08:01:04 PM »
Sorry for not keeping this thread more up to date...

We've essentially worked ourselves to exhaustion the last three weeks trying to get everything ready.  Unfortunately, we're a bust for mid-June.

This picture was taken a week and a half ago, and it's essentially the current state:


Why haven't we progressed in the last 1.5 weeks?... the answer is that CB750 engine sharing the table with the CB160 build.

My current (primary) race bike has transmission issues, due to me dropping the bike on it's left hand side during a track day last year.  After that the bike would frequently pop out of gear.  We also started seeing metal filings in the oil.  The plan was to rebuild a K2 engine I had as a replacement, but we were slow to get started on that project.  We were working on the K2 engine in parallel with the CB160, but progress was slow.  About 1.5 weeks ago we realized if we didn't prioritize the K2 engine build we might not have a working bike ready for the race.

Good news is we completed the CB750 K2 engine rebuild (2nd over pistions, APE bronze valve guides, APE valve springs, pristine K2 cam - from edwardmorris, all new transmission bearings (SKF), and the APE extra plate clutch kit) - and installed it in the frame.  So, we'll be in Grattan racing this weekend... just not with the CB160.

Our next race after Grattan is in NJ, in mid July.  So even though we're a bust on the cB160 for June, we'll definitely get her on the track in July.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline seanbarney41

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Re: Le Mans start CB160 by mid-June or bust
« Reply #34 on: June 08, 2015, 08:29:43 PM »
Hi Chris...glad to hear you are coming to Grattan again.  I am gonna try to come see some racing Saturday and will try and say hi.
If it works good, it looks good...

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #35 on: June 27, 2015, 09:04:10 PM »
Hey Sean... thanks for stopping by during the weekend!

I really appreciate the support... and it was great talking with you again.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #36 on: June 27, 2015, 09:11:39 PM »
OK... so now the goal is to get this baby on the track in two weeks, for the AHRMA Vintage weekend at the New Jersey motorsports park from July 10th - 13th.

We're getting really close... we actually got her started today.  Isn't running great, but we were very pleased with how easily it started:
http://youtu.be/YghScuz1kdk

Here are a couple pictures of how far we've come:


- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #37 on: June 27, 2015, 09:22:15 PM »
You might have noticed the wheels earlier in this thread are different than the ones on the bike now.

Just for future reference, for anyone building a CB160, the correct rim size (front and back) is 1.6 x 18.

The Excel rims below were 1.85 x 18, which I ordered by mistake. 
And then I ordered 1.4 x 18 in rims from Honda - which I was told were be better - but then I didn't like how the spokes looked with those (bowed and not correctly seated).... so I finally did what I should have done in the first place - confirmed the stock size and ordered them from Buchanan's.

It's depressing how much money I blew with this tragic comedy of missteps.

Here are the rims, laced up, with race compound tires:
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Online HondaMan

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Re: Le Mans start CB160 by mid-June or bust
« Reply #38 on: June 27, 2015, 11:18:40 PM »
Man, oh, man...just looking at it screams out, "Mike, come ride me!".
i don't know if he ever raced the 160, but I saw a shot of Mike Hailwood on one once, all tucked in...
:)

I used to have his famous poster on the Honda Six, cranked almost to the ground, hanging on my shop wall. I still regret leaving that there when I left.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline bwaller

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Re: Le Mans start CB160 by mid-June or bust
« Reply #39 on: June 28, 2015, 05:50:41 AM »
Very cool. I hope it turns out as much fun to ride as it looks! I can also appreciate the blown dough on getting wheels sorted. Good luck with it.

By the way how did the 750 work out?
« Last Edit: June 28, 2015, 05:54:54 AM by bwaller »

Offline vfourfreak

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Re: Le Mans start CB160 by mid-June or bust
« Reply #40 on: June 28, 2015, 06:05:16 AM »
OK... so now the goal is to get this baby on the track in two weeks, for the AHRMA Vintage weekend at the New Jersey motorsports park from July 10th - 13th.

We're getting really close... we actually got her started today.  Isn't running great, but we were very pleased with how easily it started:
http://youtu.be/YghScuz1kdk

Here are a couple pictures of how far we've come:




Beautiful !

Kev

Offline RAFster122s

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Re: Le Mans start CB160 by mid-June or bust
« Reply #41 on: June 28, 2015, 11:40:43 AM »
Gorgeous bike, I always loved the looks of the CB160 anx it looks far sweeter in racing trim.
What are the tires you use for racing.?
David
David- back in the desert SW!

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #42 on: June 28, 2015, 09:20:13 PM »
Gorgeous bike, I always loved the looks of the CB160 anx it looks far sweeter in racing trim.
What are the tires you use for racing.?
David

I'm using Bridgestone Battlax BT-29SS 2.5x18.  The 2.5x18 are race compound (or, at least they say they're for race only).  We hear they're a popular choice for the CB160 racers and we've seen a lot of them at the track.  That said, I don't think Bridgestone is making them anymore.  I had a lot of trouble sourcing them but was eventually able to get them from R.C. Barker (http://rcbtires.com/). 

Some sad news... when I was at Grattan two weeks ago I heard that R.C. Barker recently passed away.  Real helpful and friendly guy, I was really sorry to hear that. 
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #43 on: June 28, 2015, 09:22:39 PM »


Beautiful !

Kev

Thanks Kev.

Sorry about missing your earlier post... I definitely would be interested in the CR93 parts list.  I'm not sure if I could still source anything, but it sounds like good information to have available.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #44 on: June 28, 2015, 10:02:06 PM »
Very cool. I hope it turns out as much fun to ride as it looks! I can also appreciate the blown dough on getting wheels sorted. Good luck with it.

By the way how did the 750 work out?

Thanks for asking Brent... it was a very successful trip for us.  Just the fact that the 750 engine we rebuilt shortly before we left (and just put into the frame about a week before we left) ran without issues was really all we were hoping for.  The engine ran great, and was a real sense of accomplishment.

I also consistently improved my laps times from the previous year I was there.  About 10 seconds better lap times on average, which sounds crazy but you have to remember when I was there last year it was only my second race weekend. 

There were five of us racing in our class.  I got 4th place on Saturday and 3rd place on Sunday (I was on the tail of the guy in 2nd place but just couldn't get back in front of him).  The guy who came in first also had a CB750 SOHC... but boy was he good.  Turned out he's a race instructor (I think for young kids?).  I was able to beat him off the start  - he even complemented me after the race on how strong my engine seemed :) - but I just couldn't keep up with him.

All said, it was a great race weekend, with the five of us in our race class/group comparing notes after each race.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #45 on: June 28, 2015, 10:09:39 PM »
One of the big challenges we've been facing is just getting the correct parts ordered.

We noticed oil dripping from the front forks relatively shortly after we assembled the forks:


Turns out Honda's parts diagram specifies a 2mm x 38mm O-ring that goes in the fork seal housing... which is what I ordered from the O-ring store (since it's no longer available from Honda).  This, however, appears to be incorrect.  We looked in the shop manual (I should have double checked before) and it specifies a 3mm x 38mm O-ring - mystery solved :)

O-rings are on order.

I also had a similar problem with the oil filter/separator cover O-rings.  Most part diagrams just show the size used on a later model/year (3mm x64.5mm), but my bike (an earlier model cb160) uses 3mm x 74.5mm.  The larger one is still available from some Honda parts suppliers (Partzilla had it for me), but you have to know you need the larger one.  Not knowing set me back a few days.

 
« Last Edit: June 28, 2015, 10:16:28 PM by Kickstart »
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #46 on: June 28, 2015, 10:20:34 PM »
Here's a nice picture of the speedo blank and spacer Jeff made for the front wheel:

- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline RAFster122s

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Re: Le Mans start CB160 by mid-June or bust
« Reply #47 on: June 28, 2015, 10:29:45 PM »
Be happy you are going to be racing the CB160 and not a CA160 or CA95 with its dead end ancient anti-dive brakit right and built ng system and extremely limited tuning,  not to mention the single carb, etc.

Glad you had a good showing and no issues with the rebuilt motor.  It has to be great comfort knowing you did it right and it performs so well.
David- back in the desert SW!

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #48 on: June 28, 2015, 10:35:10 PM »
We managed to get enough completed to ride up and down the street a couple times:




I only went up and down the street twice as it was loud!

It ran pretty well... didn't seem to have much power below 4k, but felt great above 7k.
I don't have a lot of experience tuning carbs on these twins.  We're also using velocity stacks, so I'm not really sure where to even start with tuning them. 

I rebuilt the carbs between two sets, which had different sized main jets - so I used the larger of the two (I believe they were 90).  I was thinking about possibly using some of the main jets I got for my CB750, but they don't seem to thread in all the way (which is odd because they appear to be the same thread size/pitch).

It might be a good idea to see if I can source some "CB160" main jets.

 
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline Kickstart

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Re: Le Mans start CB160 by mid-June or bust
« Reply #49 on: June 28, 2015, 11:06:00 PM »
I had a little trouble getting the bike timed at first.

The advance cam for the points has two lobes on the CB160, so it opens and closes the points twice with every cam revolution.
I found that if I set the timing for the one (statically), it was slightly off for the other... I chose to split the difference, but that didn't work well. When I put the timing light up to it the F mark was jumping all around.

I decided to put a dial gauge on the advance cam and sure enough the one lobe was .002" taller than the other. 
I wasn't sure what to do... but figured it wouldn't hurt to try taking the cam off the advance and reinstall it 180 degrees from where where it was.  Turns out that solved the problem, which is great, but it's very confusing to me how that fixed it.  I double checked it with the dial indicator and I couldn't detect any height (lift) difference after I rotated the cam piece.  Odd.

With the time light, the F is timed perfectly at idle for both spark wires.  The advance is consistent as well, but it's few degrees more advanced then the advance mark.  I'm not sure if I want to mess with the advance stop tabs, or leave it.  Is a little more advance than stock good for a racing bike?

The attached picture doesn't show the dial indicator.  I put the whiteout on the high areas - because I felt like it :)

- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA