Going to the track

[jkotsi]

Thanks EMS, the volumetric efficiency question was spurred by the software. I haven't run this engine on a dyno so was using stock 79 specs as the input but not sure I have the cam info correct.

The software is the, Pipe Max program, for exhaust design. A screen shot of the exhaust page is below.

There is a DG 6-1 pipe on the bike now and a damaged set of Wolf 6-2 waiting. Since the 1st primary pipe is small diameter I was thinking of modifying the Wolf to work with the recommendations from the program. Right side of the Wolf is in good shape to measure from, left side is crashed damaged at first bend so it will need to be cut for repairs.

Pics of the Wolf to follow.

Any thoughts on welding stainless to non stainless?

[jkotsi]

Back home Sunday, time to pick up this project. Met with Denis, the frame builder, set a date to drop off the bike at his shop, Jan 16/17. I had talked to Tom before the holidays and he offered drawings of his and Roland's modifications. They were in the mail box when I got home.

Denis and I discussed mods to the frame, some of Dr Tom's mods will be incorporated, definitely welded upper mounts. Most likely a few different cut and welds but a similar result, raise the engine, lower the seat, tighten the rake, shorter trail and a shorter wheel base. Mulling over the ATK swingarm versus the stock Pro Link. I would like to try the ATK with the anti squat on the track and see how it rides. Denis's opinion is to put both back on the shelf and build a steel swinger, not going to happen in this incarnation.

Time to get into the garage and remove the bits I don't need, -12 Celsius, maybe some anti freeze before I start.


If you are interested in what is involved to modify the frames, this is a great start, courtesy of Dr Tom.

Initial modification to a 1979 CBX


Alternate mods for a similar result to a Pro Link

[jkotsi]

Rolands current state with the Beast getting some updates.

Love the height!

[steve murdoch icoa #5322]

Jim, i am not familiar with the anti-squat ATK, only seen one with the chain rollers.
How does it work?
Wouldn't a braced steel swingarm weigh a ton?

[jkotsi]

The swingarm Denis makes are CrMo, I think the weight comes in around 13lbs braced. He uses tapered roller bearing as well, a really nice piece.

The ATK has a chain roller that is suppose to reduce the rear end squat when you accelerate. Lessens the tendency to run wide when exiting a corner.

This one just sold, mine isn't painted


http://www.ebay.com/itm/Honda-CBX-Cast- ... 7675.l2557

[steve murdoch icoa #5322]

I did see that one and thought it was a great price. Pretty sure JJ on the 1100F site bought it.
I thought the rollers were strictly for keeping a proper chain tension and had not heard of any anti-squat benefits.

[jkotsi]

The added sprocket and idler wheel change the direction of pull on the chain. That is what reduces squat, most of the ATK's I have seen are not complete. The arm can be used without the idler attachment.

[jkotsi]

I have had a few delays getting the bike to the frame shop, hoping it will happen by next weekend

I have a couple of questions regarding carbs and cams. The stock carbs are due for a full rebuild and I would like to add pods or V stacks. What is the cost for all the parts required, I would be doing the disassembly/reassembly and sending the bodies out for ultra sonic cleaning?

The CRs from Tim's look great but exchange rate/shipping/duty and taxes, puts these at over $3k CDN, that's not happening. I have a rack of 31's for my 900F if I add a used pair or find a second rack of 4 to split the cost may be close to the rebuilt stock set? Any tips for building set to fit the CBX?


The cams will run with under bucket shims, the buckets need to be modified, cut the lip off the top, set a flat recess on the underside, possibly lighten the bucket. The retainers swapped out for aluminium, TL 1000 are suppose to fit. Any suggestions?

[daves79x]

As far as the carbs go, you are looking at $400-$500 in parts at least, including cost of pods and you doing the work yourself. Therein lies the problem - can you do the complete carb tear-down and reassembly yourself? There's a lot of rejetting needed for this set-up as well. However, getting the carbs correctly cleaned and put together is the biggest job and will give you headaches if not right.

Parts would include: A rebuild set from Randakk, a set of K&N pods, a pocket full of jets (for both the primary and secondary main if you have VB60 carbs). Jets run about $7 each and you'll need a bunch.

I can't help you with the shim-under-bucket issue.

Dave

[Jeff Bennetts]

I have had a few delays getting the bike to the frame shop, hoping it will happen by next weekend



The cams will run with under bucket shims, the buckets need to be modified, cut the lip off the top, set a flat recess on the underside, possibly lighten the bucket. The retainers swapped out for aluminium, TL 1000 are suppose to fit. Any suggestions?

Kibblewhite has what you need, you may need a loan though.
http://valvetrain.kpmivalvetrain.com/ca ... 79-to-1982

[daves79x]

Reviewing the thread I see you've said the engine is to remain 'pretty much stock' for now. Anything remotely near stock would not require the great expense of shim-under-bucket valve train. Is there something else now you've planned that you feel the need to do that? Otherwise, I'd put my money in lots of other improvements.

Dave

[EMS]

..also, make sure the regulations for the class you want to race in, allow the engine modifications

[jkotsi]

..also, make sure the regulations for the class you want to race in, allow the engine modifications

AHRMA allows the mods I am looking to do. The engine limits are stock displacement, unrestricted carbs, original engine cases most internal mods are acceptable. Body work to be stock, tank, seat, headlight bucket and gauges. 41mm forks, Ohlins twin shocks, F2 front and rear rims.

Reviewing the thread I see you've said the engine is to remain 'pretty much stock' for now. Anything remotely near stock would not require the great expense of shim-under-bucket valve train. Is there something else now you've planned that you feel the need to do that? Otherwise, I'd put my money in lots of other improvements.

Dave

What mods would you suggest?

I am looking at this as a multi season build, frame and suspension this season, engine mods limited to bolt-on. Likely going to try and sort out a set of 31mm CRs for carbs, 79 intake cam, under bucket mod, valve springs, seals and cam cap bolts, repair a Wolf 6-2 header, possible swap of Dyna ignition for C5.

I think 31mm carbs are too much but I can't afford 29mm this season and 31's next year. Hoping these are easier to tune than stock.

Save opening the cases for next season.

[jkotsi]

I have had a few delays getting the bike to the frame shop, hoping it will happen by next weekend



The cams will run with under bucket shims, the buckets need to be modified, cut the lip off the top, set a flat recess on the underside, possibly lighten the bucket. The retainers swapped out for aluminium, TL 1000 are suppose to fit. Any suggestions?

Kibblewhite has what you need, you may need a loan though.
http://valvetrain.kpmivalvetrain.com/ca ... 79-to-1982

Thanks, I will be buying their springs but trying to cut corners on the budget were I can. Stock buckets can be redesigned to work there are a few steps I would like to add in but cost will be a limiting factor. Boring the side and top of the bucket to reduce weight and coating the side and top to reduce friction, cams will be done as well.

Aluminium retainers weigh less than the Ti, should be less pricey as well.

[jkotsi]

Left out the sump extension, larger oil cooler, may try the mod to de aerate the oil filter, lighter battery and relocate the rear sets.