Boyesen water pump cover

Anyone run one of these,have just fitted one up and a bit wary of how far they stick out,bash plate almost covers most of it for frontal rock impacts but it looks like laying the bike over on that side would impact the water pump before anything else?

I run the boysen supercooler and have had no trouble with it. It doesn't seem nuch bigger to me. My TT store bash guard covers it completely.

I run one. No problems. I run a HYDE Bash Plate

I run one as well, I have a carbon fiber skid plate and have not had an issue.

Ill look into a new bash plate that covers it completely,anyone have pics of their bash plate and how much it covers waterpump? the only bash plate I can get locally is the one I already run so would be handy to know how it will look and coverage before ordering from overseas

bash.jpg Edited by wielywilly-g

I also added a unionless silicone hose kit I bought off ebay. Fits great and eliminates a few failure points

I have a Boyesen Supercooler on my 05 and 09 450R's.. no issues at all with skid plate. 


Big difference between the OEM/Stock and Boyesen impeller.  :thumbsup: 


Good luck. 








HYDE RACING Plate. The Newer Hyde Plate comes up higher on the water pump


Edited by GreenHornet450

Thanks for the pics guys,does the boyesen clutch cover mean more oil capacity and are they billet or cast?

Not sure about the Boyesen clutch cover, but the Hinson BTL clutch cover is billet, deeper, and holds 920cc's versus 670cc's with the OEM clutch cover.


Hope this helps.


Good luck.

Hmm I looked up the hinson one that fits the KLX450 and they don't advertise the fact that it will hold more oil,will fire off an email to them and ask.

Cast aluminum, stronger and not fragile like magnesium

Hmm I looked up the hinson one that fits the KLX450 and they don't advertise the fact that it will hold more oil,will fire off an email to them and ask.




I'm not sure about the KLX450 series aftermarket clutch covers..


I installed a new Hinson BTL slipper clutch assy with Hinson cover on my 09 CRF450R. I serviced the transmission with 85W gear oil using a ratio rite measuring cup and it took exactly 920cc's before it started to run out the fill hole on the R/H side case cover. When I was installing the Hinson cover I laid it next to the OEM cover, the Hinson cover was noticeably deeper. 


Let us know what you find out on the KLX450 cover. 



for those who swapped over to the boyesen impeller how did you remove the stock impeller? I used the workshop manual which simply says take water pump cover off and undo impeller bolt and swap over,I did that but it just kept turning so I put it in gear and  then it undid and I swapped them over,after searching for other stuff on here I came across someone asking how to remove an impeller and they were told to remove the case to get a wrench on the other side to avoid breaking the shaft or something like that,surely the manual wouldn't leave out that kind of information if you were meant to do it that way? I'm hoping that was just bike specific for that bike that was being discussed

Did if the same way you did. In gear, was pretty easy.

Thanks,I notice that you have a yoshi rs2 exhaust,how do you find it? I'm looking at a new exhaust as mine was butchered a bit to make it fit and the yoshi seem to be the best priced to land in aussie compared to the rest

The Yoshi system has been excellent. Great workmanship, sound and performance. Highly recommended.

Awesome,got my bike running today and have an exhaust leak that stopped me getting the jetting spot on,I have a pro circuit header pipe and pro circuit ti  muffler and the mid pipe size was same as header pipe size so I made it fit and has been a problem ever since,I really want to start off with a whole new exhaust that actually fits together and get the jetting spot on,very impressed after the initial test ride today,the bike feels faster than before and had only used 3/4 of the throttle.Yoshi it is.

I have the FMF Power Bomb and Q4 Muffler. Sounds Great and performs Great. MRD makes a Great Exhaust but they're a Bit Loud

Edited by GreenHornet450

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