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Cylinder Works Big Bore Kit
Cylinder Works Big Bore Kit

$442.67 - $1052.78
10% Off - Save up to $116.97

Select your bike to see if this big bore kit fits
Description See Also: 5 Reviews 19 Questions Fitment Part Numbers
Item #CYW0003

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5 Reviews
4.8 out of 5 stars
5 Star   4 4 Star   1 3 Star   0 2 Star   0 1 Star   0
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All Reviews
Verified Purchaser
Fargo nd
Durability 4/5 Ease of Installation 5/5 Performance 4/5 Power 5/5 Style 4/5
Simple to install

Am vary happy with this product simple to install and definitely can tell the increase in torc on the bottom end! Do recommend sending in your computer to be reprogramd for full power gain!

Verified Purchaser
Tn
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Good Product

I have never liked the gaskets that come with big bore kits but these actually come with oem style and fit gaskets. Theres no replacement for displacement!

Verified Purchaser
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Bad to the bone

Power difference is great and perfect. Excellent buy

Riverview, FL, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
I will buy again. Greak kit

At first I was skeptical buying this. But after reason all the positive reviews. I decided to buy this kit and a crank kit due to a engine seize I had with oem parts. I put the bike back together and it roared. Sounded meaner. After the break in period,it was hammer down with no issues at all at 15 hours in so far. Bike is running strong and great. I recommend this kit to every one who is looking for a big bore. Installation was a ease with no issue. Also have had zero over heating issues even when running in a Sugar sand feild with the Florida sun bearing down at 89 degrees out

Verified Purchaser
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
AWESOME KIT

Improves power where you need it without sacrificing anything. It;s no 450 but it does help narrow the playing field.

19 Questions
Answered:   16
Not Yet:   2
XxDirtRiderXx
Q: How many CCs does it make it 
19 days ago
Jmac
Q: I have a 2016 yfz450r i want to put this big bore kit into. What compression piston does it come with? Id like a high compression piston.
Over 7 months ago
Thumbs
Top 10
Over 7 months ago
A: This particular kit is not high compression, it's only 12.0:1. And the kit uses a specific piston that isn't offered in a high compression option.
Luke
Q: Will this kit fit on a 2009 CRF150RB
1 year 5 months ago
MotoStaff
MotoSport Staff Expert
1 year 5 months ago
A: Yes it will, just select your ride on this page and we will send you the correct item.
CJsiegel
Q: I have this kit for my ltz 400 but i blew out my piston rings how can i find replacement rings
1 year 7 months ago
Jake60
Q: Efi settings
1 year 7 months ago
I have a 2014 rmz 250 also with this i have a jd jetting efi controller what a good starting point on the on the feul settings
doodar
Q: Will this kit be available for 2016 and 2017 yzf 250's ? if so when?
2 years ago
MotoSportExpert
Expert MotoSport Staff
2 years ago
A: Please call one of our sales professionals to inquire about special orders and availability.
Dirt Bike / ATV: 1-888-676-8853
Mitch
Q: Will this fit a 2004 KTM 250 EXC?
2 years 2 months ago
MotoSportExpert
Expert MotoSport Staff
2 years 2 months ago
A: No sorry this Cylinder Works Big Bore Kit will not fit your 2004 KTM 250 EXC.
Macon
Q: Will this fit my 2005 Yamaha ttr 230?
2 years 2 months ago
MotoSportExpert
Expert MotoSport Staff
2 years 2 months ago
A: No sorry this kit would not fit your 2005 Yamaha TTR230. If one is available through one of our suppliers, we would be happy to order it for you. Please call one of our sales professionals to inquire about special orders and availability.
Dirt Bike: 1-888-676-8853
Nathan
Q: Does this fit a 2003 Yamaha yz250?
2 years 3 months ago
I have a 2 stroke 2003 yz250, will this fit? And will I need a new head cover? Also can the stock piston rod fit with it?
MotoSportExpert
MotoSport Staff Expert
2 years 3 months ago
A: Yes the Cylinder Works Big Bore Kit will fit your 2003 Yamaha YZ250. Just be sure to correctly select the Year/Make/Model of your bike before ordering so we can be sure to send you the correct kit for your bike. Will work with your stock head and crank. Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
Nathan
Q: Is this available for 2 strokes? I have a 2003 yz250. and will I need a different sized cylinder head?
2 years 3 months ago
MotoSportExpert
Expert MotoSport Staff
2 years 3 months ago
A: Yes, Just be sure to correctly select the Year/Make/Model of your bike before ordering so we can be sure to send you the correct kit for your bike. This kit will work with the stock head. Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
1 - 10 of 19
Fitment
See all bikes that this part fits...
See Fitments
# Part Numbers
Product Variant Manufacturer Part #
+3mm 11010-K01
+3mm 51006-K01
479cc 11003-K01
477cc 11005-K01
159cc 11004-K01
269cc 11001-K01
270cc 11007-K01
488cc 11002-K01
478cc 11006-K01
434cc 41001-K01
269cc 31001-K01
269cc 31004-K01
474cc 41002-K01
+3mm/478cc 21001-K01
269cc 21002-K01
478cc 21003-K01
269cc 31006-K01
269cc 31006-K02
159cc 11004-K02
256cc 12001-K01
478cc 11006-K02
478cc 11008-K01
270cc 51004-K01
269cc 31005-K01
469cc 31011-K01
276cc 51002-K01
365cc 51001-K01
365cc 51003-K01
269cc 41003-K01
269cc 41004-K01
269cc 41004-K02
269cc 21010-K01
478cc 23001-K02
468cc 21005-K01
468cc 21005-K02
103.5cc 21007-K01
727cc 11009-K01
478cc 21003-K02
727cc 21004-K01
727cc 21004-K02
727cc 21104-K01
727cc 21104-K02
107.8cc 21107-K01
860cc 31007-K01
859cc 31007-K02
975cc 61001-K01
808cc 61002-K01
808cc 61002-K02
1110cc 61003-K01