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Niche big bore kit delivered tomorrow; Any advice or questions?


cfr

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All,

Background: '05 S-model with 11k miles. Mechanic did a leak-down test and said 40% leakage through the rings and the valves are OK. Upon disassembly back at home, no cross-hatching left on the cylinder. Bike isn't worth much (bought it for $2k five years ago and thrashed it since). On the fence about scrapping the bike. So...

I thought I'd take a chance on the 434cc Niche big bore kit from PartDiscounter ($140; glacially slow shipping; same kit available on Amazon from a different seller). Information on these kits is both scarce and old. If it grenades the engine, I'm not too worried because I got what I needed out of this bike for the last 5 years. Cheapest price I could find on the Cylinder Works kit is around $500 and I can't justify that investment in this bike.

Here's what I've read/heard,

  • Very little detailed information was available and confusing but that has improved.
  • Quality used to be poor but it's improved (manufacturing defects, uneven mating surfaces at the top/bottom of the cylinder jug, etc)
  • The gaskets probably suck
  • Most that install these disappear on the forums after reporting initial success (never know if it grenaded and they don't want to admit it or if it is working fine)
  • Plenty of skepticism all around (myself included)

As a double-check on the application of this kit for this bike, the cylinder works part numbers are the same for the KFX400 and the DRZ400 (implying that any kit for the KFX400 should also work on the DRZ). Additionally, the vendor confirmed compatibility.

The kit should be arriving tomorrow and I'll take close up pictures of what's in the box and post them here.

Anything you want to know/see pre-install when I'm looking at the parts?

Thanks,

-Charles

 

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5 hours ago, cfr said:

The gaskets probably suck

They might be an easy change for better success.   Cometic gaskets are OEM and Cylinder-Works choice - see if you can rustle up a big bore set to replace the supplied? - especially if the supplied are anything other than the metal coated type.

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I know there is a write up here, copper coat spray, and a bit more torque. My bb gasket failed, I re did it with cometic gasket and copper spray, now it’s all good.  You can also switch to single layer base gasket for more compression while you are in there. Also check fit, there is at least one rivit that needs taken out or it will interfere with the head 

Edited by bronco1968
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I scored a new forged vertex piston on Amazon for $30 a few years back. There was nothing wrong with the original top end so I waited and debated what to do. Took a chance on a knock off 94mm bore cylinder from eBay. The brand name escapes me but it was $100 so I bought it. Vertex piston was a “c” size so like a hundredth oh a mm bigger than normally supplied in the name brand kits. Ring gap was fine so I used it. Installed with 94mm cometic gaskets. Cut out the base gasket to single layer. All works fine years later. Uses no oil in 1000+ miles.

91 octane fuel minimum in this setup. 

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2 minutes ago, SC_lurker said:

I scored a new forged vertex piston on Amazon for $30 a few years back. There was nothing wrong with the original top end so I waited and debated what to do. Took a chance on a knock off 94mm bore cylinder from eBay. The brand name escapes me but it was $100 so I bought it. Vertex piston was a “c” size so like a hundredth oh a mm bigger than normally supplied in the name brand kits. Ring gap was fine so I used it. Installed with 94mm cometic gaskets. Cut out the base gasket to single layer. All works fine years later. Uses no oil in 1000+ miles.

91 octane fuel minimum in this setup. 

I have read that the piston brand is more important than the cylinder 

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I've actually installed two of these with good results, the supplied MLS gaskets work fine. You will need to dry fit and most likely remove most rivits. Proper install is the key. If you get oil on the gaskets, brake cleaner on a rag will remove safely. If you got the quad kit you may have to drive out the crank vent nipple and reposition correctly. I used a drift on backside, turned with pliers then drove back in with appropriate sized socket. In all honesty the cylinders have been better than the last two Cylinder Works kits I used and had to send in for replacements.

First one I installed had over 8,000 miles last I knew. I checked it at 5,000 miles and it had less than 2% leakdown. Second kit still has low miles, no issues as of yet. I did take a file and hit the bottom edge of the piston as they seem really sharp, when you get it you'll understand. I used the dry piston install method and always a new OEM cam chain

 

 Good luck!

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Good advice is to wash the new cylinder good with dish soap and dry before installing. I use assembly lube on the cams before putting it all back together. Ride it for a long ride then drain the oil and refill and replace the filter.

Ebay cylinder I used was sold under the Caltric brand.

Edited by SC_lurker
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Got the kit and got it out on the kitchen table. Pictures below. Here's what I noticed,

  1. No instructions
  2. Jug looks good.
  3. Two wrist-pins included. No idea why.
  4. Good marking on the top of the piston for orientation.
  5. Notch for clip on side of piston has a piece of metal that would break off. Will file down.
  6. Little bit of a sharp edge on the angled parts of the piston skirts. should probably knock that edge off.
  7. Piston skirts are coated
  8. Rough casting at the very bottom of the part where the wrist pins go
  9. Gaskets don't look like garbage (paper or cardboard).
  10. Don't know what the four copper washers are for but assume the four head bolts that hold the head and cylinder to the rest of the engine.

Next steps,

  1. File as described above
  2. Check gaskets vs OEM for both correct size, holes, etc.
  3. Separate base gasket for higher compression like E-model.
  4. Look closely at the new piston vs the OEM for differences
  5. Compare wrist pins with OEM to figure out which one to use
  6. Check the ring gaps but don't have a spec. Probably use OEM or Cylinder Works?
  7. Check fit of top/bottom of jug surface for gaps, wobbling, etc
  8. Wash and clean piston and cylinder (a bit dirtier than expected)

Upon installation,

  • Be careful
  • Spray both sides of head and base gasket with permatex copper gasket sealant the night before installation
  • Use assembly lube on wrist pin
  • Avoid flame war on dry ring installation vs oiled 🙂
  • Make sure to torque the head bolts to 42.5 ft-lbs (clymer is wrong)

Missing anything?

Thanks,

-Charles

kit.jpg

piston-kit.jpg

jug.jpg

jug-bottom.jpg

jug-top.jpg

piston-bottom.jpg

piston-side.jpg

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Additional observations on the piston compared to the OEM.

  • The skirt is shorter than OEM (further down the cylinder wall) but is wider (covering more of the cylinder wall on each side)
  • There are only 2 oil holes on each side (in the slot for the oil rings) compared to 3 on the OEM
  • The two wrist pins appear to be identical when measured with calipers
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Do not use the supplied copper/brass washers, def no need for the permatex and also toss their supplied exhaust gasket. As for the dry install no doubt you read Erik's write up on here. I personally spray WD40 on a rag/paper towel and wipe down the cylinder after washing with soap and water, then the thumb size spot of oil applied to the piston skirt and smeared around on it, don't get any on the rings. Make sure to have some oil on head bolt threads and washers, too much and it will get on your base gasket. 

Make sure you don't get oil on the head and base gaskets....again, brake cleaner on a paper towel is your friend.

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Looking closer at the gaskets and reading a lot more. The kit shipped with both E and S base gaskets. Using the single-layer base for the E.

Also, no copper spray on the base but two coats on each side of the head gasket.

As mentioned, the exhaust gasket seems weird (constructed differently) compared to the Suzuki one I have on hand and will use.

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On 10/20/2021 at 3:40 PM, cfr said:

Additional observations on the piston compared to the OEM.

  • The skirt is shorter than OEM (further down the cylinder wall) but is wider (covering more of the cylinder wall on each side)
  • There are only 2 oil holes on each side (in the slot for the oil rings) compared to 3 on the OEM
  • The two wrist pins appear to be identical when measured with calipers

It is also cast as opposed to the OEM piston being forged

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On 10/20/2021 at 8:45 AM, cfr said:

All,

Background: '05 S-model with 11k miles. Mechanic did a leak-down test and said 40% leakage through the rings and the valves are OK. Upon disassembly back at home, no cross-hatching left on the cylinder. Bike isn't worth much (bought it for $2k five years ago and thrashed it since). On the fence about scrapping the bike. So...

I thought I'd take a chance on the 434cc Niche big bore kit from PartDiscounter ($140; glacially slow shipping; same kit available on Amazon from a different seller). Information on these kits is both scarce and old. If it grenades the engine, I'm not too worried because I got what I needed out of this bike for the last 5 years. Cheapest price I could find on the Cylinder Works kit is around $500 and I can't justify that investment in this bike.

Here's what I've read/heard,

  • Very little detailed information was available and confusing but that has improved.
  • Quality used to be poor but it's improved (manufacturing defects, uneven mating surfaces at the top/bottom of the cylinder jug, etc)
  • The gaskets probably suck
  • Most that install these disappear on the forums after reporting initial success (never know if it grenaded and they don't want to admit it or if it is working fine)
  • Plenty of skepticism all around (myself included)

As a double-check on the application of this kit for this bike, the cylinder works part numbers are the same for the KFX400 and the DRZ400 (implying that any kit for the KFX400 should also work on the DRZ). Additionally, the vendor confirmed compatibility.

The kit should be arriving tomorrow and I'll take close up pictures of what's in the box and post them here.

Anything you want to know/see pre-install when I'm looking at the parts?

Thanks,

-Charles

 

I have a Niche BB kit on my 400.

It has travelled 9,000 HARD, high revving Kilometers over the last 2 years.

It even survived 240km with NO OIL PRESSURE, due to a broken pump gear.

I used all the supplied parts. 

There is nothing wrong with it.

Install it and ride. DO NOT USE COPPER SPRAY. 

DO NOT TORQUE THE HEAD OVER 40 ft/lbs. 34 is Suzuki's figure. It is not a misprint. 

If you want to needlessly stress out, ask everyone for their opinions about your kit !  😆

 

 

Edited by Tony Wyp
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11 hours ago, Tony Wyp said:

I have a Niche BB kit on my 400.

It has travelled 9,000 HARD, high revving Kilometers over the last 2 years.

It even survived 240km with NO OIL PRESSURE, due to a broken pump gear.

I used all the supplied parts. 

There is nothing wrong with it.

Install it and ride. DO NOT USE COPPER SPRAY. 

DO NOT TORQUE THE HEAD OVER 40 ft/lbs. 34 is Suzuki's figure. It is not a misprint. 

If you want to needlessly stress out, ask everyone for their opinions about your kit !  😆

 

 

Why do you say no copper spray, do you just find it is not needed, or have you had problems with it?

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16 minutes ago, bronco1968 said:

Why do you say no copper spray, do you just find it is not needed, or have you had problems with it?

I eventually blew the head gasket when I used it and torqued to 43 lbs.

Installed a new gasket clean and 38 lbs and have had no problems.

The metal head gaskets have a special coating  which sticks to the aluminium, when heated. I found this information later, online. 

Edited by Tony Wyp
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Got this done and started for the first time last night. Just got back from a 5 minute ride and then will look it over again over for leaks.

Rookie mistakes to avoid,

  • Don't drop one of the alignment pins for the cylinder into the crankcase. Oops. Lots of turning the crank by hand and magnet fishing. Ended up bending the pin and had to wait for new ones to arrive.
  • Mark the outside of the cylinder with a sharpie indicating the intake and exhaust sides so that you don't get confused over and over again.
  • Unless you've done it before, use a piston ring compressor. I tried like 20 times without one.
  • Don't replace itty-bitty screws elsewhere on the bike with stainless steel ones. Inevitably, you'll drop these into small places where you can only reach them with a magnet and some stainless isn't magnetic.

Thanks for the advice and comments. I'll report more as details materialize.

-Charles

 

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