Topic: Cheap 836 kits back on ebay...$110! *Update!

[RandyBMC]

I have the CruzinImage set, which look really nice.

I have a question as I'm assembling now.  For those of you who have installed these successfully, which way do the rings go.  The machine shop set the ring gap (nice of them), but removed the wrapping for the rings.  Here is what I am guessing from general building knowledge, but I am looking for correction/confirmation:

-There is no pip or mark to notate top on the rings
-The silver edged ring is the top ring, since the chamfer on the outer edge is on top and bottom
The black 2nd ring is blocked (square) with no slant for "scraping" the cylinder for break-in so there is no up or down orientation

These are questions, not statements.

Thanks in advance for any help!

[Garage_guy_chris]

Regarding ring end gap:
A zero would have been forgotten  it should be 0.010 - 0.012"   

generally they say 0.004" x bore in inches (2.560") = 0.010"

Alternately generally the service limit is about double the ideal clearance so 0.028" halved = 0.014" 

so in my mind 0.010 - 0.014" seems about right and the forums seem to back this up in multiple threads. Mine is going together with 0.012" throughout.

Regarding the order of the rings:
 which there seems to be a little confusion ( maybe just me)  it seems:

1st groove  = chrome beveled rings
2nd groove = black squared rings
3rd groove  = oil rings

We should put a sticky together with all the pertinent information regarding these kits,

[RandyBMC]

Yeah I saw that, which was helpful.  My question was just whether or not the rings had an up/top orientation since there is no pip/mark on the ring surface.

[redtractor]

Yeah I saw that, which was helpful.  My question was just whether or not the rings had an up/top orientation since there is no pip/mark on the ring surface.

I would like to know the answer to this question also, I think Hondaman has installed these kits in the past so he should know if anyone does.

[hotdog]

From memory the rings were non-directional when I installed mine....I'm sure others will correct me if I'm wrong.

[Imago]

Is this the same set @ $119.99?

http://www.ebay.ca/itm/Honda-CB750-750K-SOHC-1969-1978-836cc-65mm-Big-Bore-Pistons-Kit-w-Head-Gasket-/111782483645?

This question may have been answered already, I have to admit I didn't go through all 16 pages of this thread...

[Powderman]

Is this the same set @ $119.99?

http://www.ebay.ca/itm/Honda-CB750-750K-SOHC-1969-1978-836cc-65mm-Big-Bore-Pistons-Kit-w-Head-Gasket-/111782483645?

http://www.ebay.com/itm/69-77-HONDA-CB750K-836cc-BIGBORE-PISTON-KIT-W-GASKET-CI-CB750KBB-/161819438441?hash=item25ad30ad69&vxp=mtr
This question may have been answered already, I have to admit I didn't go through all 16 pages of this thread...

It is A kit for the CB750, but it is not the CruzinImage kit being discussed. Your seller has 2k rating and CruzinImage has 10x's that, and have a reputation for a quality product.

[Phoenix]

I strongly agree we need a sticky on this.  Put all the clearances in one place.  I asked Cruizin and he responded that there is no top or bottom on the sets.  They are not marked but it doesn't matter.  hth.

[PeWe]

Do not forget the other cheap parts when order the 836 pistons from http://stores.ebay.com/cruzinimageco1484/
Additional 65mm head gasket, clutch plates etc etc.

[5thofhonda]

So the general consensus is that this is a great option, but be wary if using an aftermarket cam?  I'm on a budget and haven't done anything like this before, so I'm torn between this and a Wiseco kit.

[Garage_guy_chris]

You have to be careful anytime you start mixing and matching performance parts and building performance engines. There are a lot of variables that can effect the outcome and ultimately the fate of the engine. My little experience with the D grind cam is directly related to a short cylinder block and the pistons coming out of the deck by 0.012" where they should be 0.025" in the hole. I ended up using a F2 cam which provided the extra needed clearance.

 If you don't want to do a lot of research and take the time to do all the critical checks and measurements then your better off just rebuilding with a 0.5mm or 1.0mm over kit with stock cam and valve train, rather than 4mm over with built heads, valve train and performance cams.

On another note my cruzin-image kit is up and running and running it does! I have got 400 miles on it now and enjoying every minute!  with my setup its a sweet roll on at 3000rpm and by 5500 you better be holding on tight. by 8000rpm its like

[hotdog]

So the general consensus is that this is a great option, but be wary if using an aftermarket cam?  I'm on a budget and haven't done anything like this before, so I'm torn between this and a Wiseco kit.

Just get the Cruzinimage kit, if you're on a budget they can't be beat. I installed my own set as well as a lot of other folks on this forum with no issues at all.
Wisecos are nice but for an everyday rider I'd go with these every time, if I was building more of a performance oriented engine - then I would go with a better higher spec piston kit.

There are a lot of drop in cams available that will cause no issues with these pistons, but be warned if you start to push the envelope with massive lifts/durations you had better be squared-away with your clearances. The fact that you're looking at these pistons tells me that things will be kept conservative, possibly look at a cx1 from cyclex (webcam #41) or a cx2 if you're more adventurous.


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[5thofhonda]

I just want enough power to have fun zipping around town. Don't plan on much highway time so might experiment with sprockets as well. Finally found a local shop that will machine something that isn't a Harley, so I'll definitely have to pick one of these up.

[Yoshimatic]

I have fitted one of these kits to one of my Hondamatics and it goes strong. The Hondamatics have small 26mm carbs and a gay cam so I fitted a standard cam from an early K model and also the 28mm carbs from an early K model. I am tempted to try my Yoshi Daytona cam just for curiosity sake and then try my F2 cam.

[Ilja]

Hi Guys, just thought I'd pop in and show you my Cruzinimage 836cc build.

Check out my topic: http://forums.sohc4.net/index.php/topic,127179.25.html

Kit is running fine.. even with the extra abuse from the turbo.
Offcourse, only got limited miles racked up yet.

The only thing I was worried about is the gudgeon pin circlips... those were VERY thin... Would like them to be a bit beefier.
Then again, I also bought a Cruzinimage XL600 103mm piston to fit in my XR600 for 666cc... and this piston had proper clips!

[HondaMan]

Yeah I saw that, which was helpful.  My question was just whether or not the rings had an up/top orientation since there is no pip/mark on the ring surface.

I would like to know the answer to this question also, I think Hondaman has installed these kits in the past so he should know if anyone does.

Yep, all the rings in all these CruisinImage kits I have used (and have on hand) are non-directional. Chrome ring on top, cast (black) in the middle. They even sell individual ring kits (don't ask...) if you really need one. Moral of the story: install rings with a good light, or maybe younger eyes?

[harald]

Can I use cruzinimage head gasket. Are they up to the job or should I get a cometic CFM-20 head gasket for my big bore?

[HondaMan]

Can I use cruzinimage head gasket. Are they up to the job or should I get a cometic CFM-20 head gasket for my big bore?

The Crusinimage head gasket will hold compression up to 10:1 CR. Above that you may need a stronger head gasket. If you drop in this kit on a K0-K6 engine it comes out to about 9.2:1.

[Phoenix]

Just got my heads back from JMR and snapped a #2 cast iron piston ring for a Honda 750. Cruzin is on vacation.  Does anyone have an extra set [3 rings] of rings they'd be willing to sell. If so, please e-mail me.
Thanks,
Ed

[MRieck]

Just got my heads back from JMR and snapped a #2 cast iron piston ring for a Honda 750. Cruzin is on vacation.  Does anyone have an extra set [3 rings] of rings they'd be willing to sell. If so, please e-mail me.
Thanks,
Ed

Slow down Ed. That's for an 836cc piston correct?

[Phoenix]

Yup Mike.  As you are well aware.   Should have mentioned it in the text instead of just putting it under the heading.
Ed

[koendd]

I can't find the piston kits in his listings?

[mrfish2]

I can't find the piston kits in his listings?

Both the 750 kits and the 550 kits haven't been listed for a little bit now, I'm sure it won't be long before they're back in stock.

[Ilja]

Recently I've managed to blow my Cruzin-image pistons (blown some ringlands and pinched a ring tight between ringlands when experimenting with boost) and I decided to just order a new kit.
I don't want expensive forged pistons that I have to setup loose for my street-turbo...so in goes the Cruzin pistons again!

So, the new pistons came in after waiting 1 week and they seem to now have directional piston rings, with marks on them!

By the way, these pistons have a slight dome of 1.5mm high, something like 2.5cc. You need to take that into account calculating compression.
And, if you run very tight squish (1mm), you might need to machine the outer ridge of the pistons so its parrallel to the head.

[madmtnmotors]

By the way, these pistons have a slight dome of 1.5mm high, something like 2.5cc.

Have you got some picts? My last set of 65mm pistons from C.I. were flat top. The domed version would likely work better in the later K7/K8 since they had a slight dome as well.