Cylinder Works Big Bore Cylinder Kit

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Cylinder Works Big Bore Cylinder Kit
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Cylinder Works Big Bore Cylinder Kit

Our Price: $442.67$944.82

MSRP: $491.85 - $1049.80 - You save up to $104.98 (10% off)

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Additional Videos

Cylinder Works Big Bore Cylinder Kit

Cylinder Works

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Details

    Cylinder Works Big Bore Cylinder Kits set the standard when you want to increase the displacement of your motorcycle, UTV, or ATV. With this kit you get top quality parts rolled into one package so you’ll be able to directly fit every component, torque everything down, and get back to riding. The cylinder itself is made from an OEM grade aluminum casting with a nickel silicon carbide cylinder sleeve that comes precisely sized and honed, giving your engine great ring sealing and cylinder wall longevity. The dimensions of the big bore cylinder are sized to fit your stock engine without any machine work or modification. And to make things easier for you, the kit also includes the correctly sized piston, rings, wristpin, and gaskets to fit your new larger displacement bore perfectly.

    If you want to get more from your machine, pick up Cylinder Works’ Big Bore Cylinder Kit to give your ride with a whole new attitude.

    Specs:
  • Nickel Silicon Carbide plated cylinder
  • Bore comes properly sized and honed
  • Easy bolt-on installation
  • No machining or alteration of your engine or cases needed
  • Kit comes complete with cylinder, gaskets, and piston kit
  • Replacement piston kits and gaskets available
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Cylinder Works Big Bore Cylinder Kit Reviews

Each review submitted enters you into a
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
 
4.5 / 5.0
44 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
34
5
2
0
3
Value
4.6 / 5
Durability
4.6 / 5
Fitment
4.9 / 5
Performance
4.7 / 5
Recommend it?
Yes (24)
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
MXA and Rocky Mountain Both said install with no further mods.
But it really needed an ecu reflash on my 17 KTM 250sxf or it wouldn't really run. Sent to Tokyo Mods For reflash, That helped quite a bit, The terrible 17 KTM battery needed to be replaced for a bigger one. and the TPS had to be adjusted. Now with all that done and behind me, IT REALLY RIPS. im about 190lbs and it really helps my corner speed with that little extra oomph, i also went to 14/49 gearing and its pulling great.

-m-2017 KTM 250 SX-F--
September 30, 2018
orlando, FL, US
Age: 25-44
Purchased
4 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
4 / 5
Recommend it?
Yes
Ktm 365 big bore kit
This kit gives the 350 what it lacks in the middle of the power band. Seems to be a little lean so I sent the ecu to Tokyo mods to reprogram. Overall the big bore kit is more than I expected.

-m-2016 KTM 350 SX-F--
September 5, 2018
Lake Havasu City, AZ, US
Age: 45-64
Purchased
3 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
A++ on cylinder works big bore kits
I've always been happy with all of the cylinder works big bore kit's I've installed. Fit and finish and performance is top notch. Another thing to always think about when installing a big bore is how much time is on the crank. You're bolting on more horsepower, how long will the used crank hold up. Hot rods crankshafts are a great product!

-m-2008--
August 23, 2018
Lincoln, NE, US
Age: 25-44
Purchased
over 2 years ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
5'7 - 5'9
Value
4 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
4 / 5
Recommend it?
Yes
Good
I would definitely recommend this product to anyone looking for more power. simple to install and good craftsman ship

-m-2007 HONDA TRX 450ER--
July 18, 2018
Bigelow, AR, US
Age: 25-44
Purchased
8 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Cylinder works big bore kit
I bought this for future use.

-m-2012 KTM 350 SX-F--
May 17, 2018
sprague river, OR, US
Age: 45-64
Purchased
7 months ago
Gender:
Male
Weight:
251 - 280 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Best bang for your buck
Night and day difference installed on my drz400sm paired with stage 2 hot cams

-m-2015 SUZUKI DR-Z 400SM--
March 2, 2018
Felton, DE, US
Age: 25-44
Purchased
9 months ago
Gender:
Male
Weight:
131 - 160 lbs.
Height:
5'4 - 5'6
Value
4 / 5
Durability
4 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Worth the money if needed a bit more power
Made my 2014 sxf 350 pull nice. Id give it a 5 but the only reason i didnt is because it really works much better with a jdjetting tuner of something similiar to really make it shine! Nice power at a lower rpm and "lofts" the front wheel easier now. Nothing negative ro say about thw kit whatsoever! Was going to get a 450 but was cheaper to try this and glad i did! Still not thw torque of a 450 on bottom but pulls great and does not sign off early....just keeps pulling.

-m-2014 KTM 350 SX-F--
User submitted image
Added Nov 21, 2017
November 21, 2017
Gentry, AR, US
Age: 25-44
Purchased
1 year ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
oh yeah
Needed a top end so spent the extra dough for this BBK. the 270 was recommended by a top local KTM mechanic for reliability reasons. Wow the mere 20CC improvement over the stock 250 was worth every penny. Basically kept me from selling the bike. Already had the EFI re-map'd & full fmf system.

buy this BEFORE an exhaust system and thank me later.

-m-2014 KTM 250 XCF-W--
October 11, 2017
op, KS, US
Purchased
1 year ago
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Recommend it?
Yes
Cylinder Works 269cc BB
Let me start off by saying wow. This kit brought my bike alive. It has been 11 months since I installed this kit on my bike. I have been to 17 races since installed and I run two classes, 250B and 25+. I have had zero issues, just ordered the parts to freshen it up after the next race and hopefully make it another year. By the way I bought this bike new and it let go 3 months in which is why I bought the big bore. Def reccomend.

-m-2016 YAMAHA YZ250F--
September 26, 2017
Rogersville, TN, US
Age: 25-44
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Fitment
5 / 5
Performance
5 / 5
Cylinder Works Big Bore
I am 215lbs. Made my RMZ rip! Added the stage 2 cams and exhaust but so simple and makes the bike so much fun to ride. It pulls harder on top than before with the cams and pipe along with the added bottom and mid. Total package. Worth it. Makes more power and is reliable.
September 1, 2017
Fullerton, CA, US
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Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 22 questions Browse 22 questions and 56 answers
My bike is fuel injected. Would I need to adjust the fuel controller on a dyno after this kit?
Jerry M on Nov 22, 2016
BEST ANSWER: Yeah, you'll most likely need to adjust your EFI to compensate for the extra fuel needed with this kit.
I have a 2013 polaris razor 4 800 I need more power I love the width of my machine i do not want a 900 or 1000 what are the best options?
A shopper on Oct 1, 2016
BEST ANSWER: Big bore kits have worked very well for me. My experience has been with KTM 350 and RMZ 250. The added performance was concentrated mainly in the lower rpm and midrange rpm. Made getting into the meat of the power much easier. Plus if you are mechanically inclined it's easy to install and comes with everything you need. Far better results than buying an exhaust system and more reliable than going for a high compression piston. No issues with reliability. Have friends that have added big bore kits to their utv's and the results were the same. Go for the big bore kit.
Do you have a choice of compression ratios for the big bore kit ?
Thomas W on Nov 20, 2017
BEST ANSWER: They are fantastic. Made my 2014 Yz a monster.
Will i need to change my jets to suit this kit, 478cc bore kit onto at 2007 450 raptor? cheers
Alex F on Aug 13, 2018
BEST ANSWER: yes, you will have to richen the pilot jet and lean out the main jet. that sounds odd but because of the larger cylinder the volumetric pressure increases so the bike actually pulls more fuel at high rpm requiring the leaner main. at idle it needs more fuel so that is why the pilot needs to be richened
What piston does it come with?
A shopper on Feb 13, 2018
BEST ANSWER: My 365 kit for a '12 KTM 350 SXF came with a Vertex piston (standard compression). Everything went together perfectly and added more bottom-end torque and power. I definitely recommend the kit!
Do you need to put different jets in the carb after install of a 434 big bore kit on a Suzuki Z400 ATV?
A shopper on Jan 31, 2017
BEST ANSWER: Typically the answer to that question is no. However the fact is you are changinga very important part of the motor. Not only are you bolting on power, but you are also changing the motors internal volumetric preasure. In order to make the very best of your new cylinder and piston combination, it is important to start w a clean air filter, new spark plug and start by reading spark plug and burn patterns. You want a nice caramel color on the electrode to insure you are having a nice and complete burn. Also make sure you have properly adjusted your valves.
Does this kit work with the stock head?
bobby s on Nov 29, 2016
BEST ANSWER: Yes, it works with the stock head. I just installed it 2 weeks ago. The installation was very straight-forward considering that I've never completed a top-end rebuild. However, the supplied gaskets are slightly different material than the stockers. It has given my 2012 350 sxf a noticeable low-end boost and I haven't had to make any mapping changes so far.
Do you have to revalve after doing a install of a 270 big bore kit?
A shopper on Jan 17, 2017
BEST ANSWER: No you do not, but it wouldn't be a good idea to put valve seals in and to set the valves and reset them again after its broke in !
Does this require case mods on the 05 crf250x?
Marc A on Nov 17, 2018
BEST ANSWER: No, everything went together easily, just don't drop the chain
Are the ring end gaps set on the big bore kit ?
Thomas W on Nov 20, 2017
BEST ANSWER: Ring end gap has been perfect on every Cylinder works big bore kit I've installed. However, ring end gap should be checked every time before assembly.
i have a 2012 kx 250 f fuel injected, after intall this kit , what do i have to do with the fuel injector sistem?
Marcelo s on Mar 7, 2017
BEST ANSWER: You will likely have to refer to a Kawasaki manufacturer for verification. However, I was fortunate with my 2012 350 sxf and didn't have to do anything with the fuel injection. The bike ran great from the time I installed it.
Is this nikasil plated?
Brandon B on Oct 18, 2018
BEST ANSWER: They are not nikasil plated but do come with Vertex pistons (for the KTM bikes).
Will this big bore kit work on a 2016 KTM 350 EXC-f, six days?
Randy H on Jul 14, 2018
BEST ANSWER: yes this will fit your 2016 KTM 350 EXC-f six days
I also have a 2013 razor 4 800 will I need to pull the motor or can i install this in place? any idea how much power over stock this will give? Will I need the fuel programmer for more fuel/air flow?
Thanks, Tim
A shopper on Jan 20, 2018
BEST ANSWER: You can do it right in the frame.. no you don’t need s programmer
Will this kit work with Hot cams stage one intake and exhaust cams on a 2015 yz250f?
joseph p on Sep 22, 2017
Cylinder Works Big Bore Cylinder Kit
Cylinder Works Big Bore Cylinder Kit
Hot Cams Camshaft (Stage 1)
Hot Cams Camshaft (Stage 1)
BEST ANSWER: Yes, but you will have to re-map it
I own a 2015 KTM 350 xcf-w six days will the kit for the 350 xcf fit my motor?
GAVIN D on Jan 21, 2017
BEST ANSWER: No, it will not work with the 350 XCF-W.
Do i jave to run tace fuel woth this big bore kit?
Tim G on Dec 13, 2016
BEST ANSWER: No you do not have to run race fuel with this kit.
can i get this kit with a high compression piston?
ERIC A on Dec 8, 2016
BEST ANSWER: Unfortunately where this is a kit we cannot switch out parts from it.
hi i have a 04 kx250f if i buy the big bore kit do i have to get a after market rod? or will any stander rod work?
richard g on Nov 14, 2016
BEST ANSWER: You can run the stock crankshaft and connecting rod.
What is the ratio to this big bore kit?
Gerald L on Nov 10, 2016
BEST ANSWER: This is a standard compression kit so it will match your stock piston compression. What machine do you have?
I'm looking for something for my 2012 750 in your kit. Do you have something for me ?
Lawrence D on Sep 19, 2016
BEST ANSWER: To see if this part will fit your machine please enter the make, model, and year into our "Choose a vehicle" drop down boxes found above the product image. If your machine is not listed, we may not carry the right item for your application.
will this bottom end kit work with big bore kit?
A shopper on Aug 29, 2016
Cylinder Works Big Bore Cylinder Kit
Cylinder Works Big Bore Cylinder Kit
Hot Rods Bottom End Kit
Hot Rods Bottom End Kit
BEST ANSWER: Yes, it will work with a big bore kit.
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