Dr. D wet sump install - product review

I installed the wet sump kit from Dr. D. today. Total cost with shipping and tax was $167.

If you had to have someone do this for you, the labor would most likely be more than the cost of the kit. It takes a couple of hours to do it right.

Here's what I don't like.

1. The caps are red. 7 all together. I understand it's a Dr.D thing, but it stands out a bit much for a bike that's blue. Doesn’t look very factory.

2. The instructions skipped the re-install of the oil pump design. Major oversight. I had to fully understand the nature of the re-design before I was comfortable knowing that the mod to the oil pump would do its job correctly.

3. The instructions did not include a "tools needed" section. I really don't care, but for less equipped shops, you would want to know that you'll need the right stuff for pulling the clutch and some small c-clips off.

4. The oil site window does not work. Unless I'm really missing something here, I can't figure out how they thought oil from the sump would get past the shift drum for a proper read. With 850cc of oil as spec'd, and with one run up, I have yet to get a visual. Major oversight.

5. The kit did not include the rubber plugs for the vent hose that runs from the top of the valve cover to the top of the frame sump. This is however, included in the photo via the web site. I don't know enough about the internals of the head design to know if oil would flow from the head to the now closed frame sump. If this was the case, if you flipped the bike or placed it on it's backside for fork valving, you could lose and trap a significant amount of oil and not know it. In either case, it's a quick fix and I can't imagine that many people let their bikes sit up side down for too long.

6. Getting oil into the magneto cover is a bit tricky. You can only use the small hole, so it's best to put the bike on its side, unless you custom make a small funnel with a 90 at the end. Not that big of a deal.

7. The instructions say that the kit includes new screws for the site glass, but it doesn't. No big deal, because the factory ones work fine.

8. The instructions should apply a little more caution about the proper fit of the site glass. You should allow the site glass holder to press in the site glass in order for a good seal between site glass and retainer. It’s just a matter of doing it better than what would function.

9. Lastly, it would have been nice for Dr. D. to share his thoughts on what oil to use. Not that big of a deal, but it’s would have polished things off a bit.

Now, here's what I like.

1. The quality of the pieces in the kit are very well machined. Everything fits very well, and with the exception of the above, they have provided everything possible for doing this conversion correctly.

2. The cost is low for the fact that you get the design knowledge and the manufacturing of the pieces. In other words, it would cost you just as much, if not more, to build this yourself.

3. It eliminates a lot of junk and makes the engine area look a lot simpler and cleaner.

4. It still uses 850cc of oil!

5. The instructions have very good photos and good step-by-step details. There's room for improvement, but based on others that I have seen, Dr. D is a step ahead.

6. I like the fact that they include everything you need to seal off the frame, including a plug to replace the frame drain plug. They could of skimped here but didn't.

7. Everybody at Dr.D was very pleasant to deal with. No attitudes.

8. Lastly, one has to consider the fact that there is a lot of liability here in them taking this item to market. That took some courage and I respect that. I just hope that most installers and users stick to the rules.

Results –

So I was not able to weigh what I removed, but at the moment my bike is checking in at 235 lbs with all fluids but fuel. My last weight check was 239, and with consideration to some other mods I've done in the last few days, I think their estimate of a 3 lb. weight loss is moderate.

So, is this product for you?

If you’re into trimming a few pounds, there are other areas on this bike that need attention before you start running less oil. But when you get towards the end of things to do, this is good stuff for the money.

Casual trail riders and those that don’t want to be bothered with more frequent maintenance may find the calculations of when to change oil to be troublesome.

So I guess you’ll have to decide for yourself.

Hope this helps.


Great report, Dave. I was just looking at this kit yesterday on Dr. D's site. I seriously doubt I would be in the market for this kit, but it is still a pretty trick mod, if you ask me. I wondered how difficult it would be to install the kit. Now I know!

Thanks for the thorough report. :)

Good info Dave. Did Doug or Gina Dubach indicate that the would consider your questions/findings and maybe tailor the kit to address them? This looks to be a very good way (for the $) to shave weight, especially since most of it is removed from up high on the bike! What's your thoughts on the frequency of oil changes. I consider this to be mostly a MX mod as most people riding much longer races will view the 1 hour of hard riding/racing interval impractical.

How far does the engine need to be tore down to do this mod.


The only serious work on the engine is the right side.

You need to drain the oil and the water, and then pull the entire clutch out. Then you remove the right case. You'll also need to remove the rear brake and kick lever.

You can leave the clutch cover, water pump, and oil filter in tact if you want, but you do have to disconnect it from the radiator.

Then you have to remove the oil pump drive gear, then the oil pump itself.

Since the oil pump is actually two pumps, you are removing and discarding the second of the two. Then to install the new flow plate, you have to pull off a small retaining clip and pull the secondary rotor off.

All of this can be done with simple tools and by hand (nothing is pressed), but you'll need the right tools to remove the clutch (holder, 30mm socket..etc.)

There is no need to remove the engine.

However, it may be wise to get new clutch housing and side panel gaskets, and a new locking tab for the clutch nut.

If you have ever done any significant engine work before, say like a top end, this job is in the easy category. For those that have never opened up an engine case before, but have good mechanical skills, you'll do fine if you just take your time.

Hope this helps.


Thanks DaveJ

I was going to order the Dr. D WS for my 250F and was wondering what I was going to get into, but just going through the right case wont be any problem. Thanks again

To DaveJ:

I was wondering what other mods you considered to be better as far as weight savings. I put the Thunder Alley on already so my exhaust is done, new TAG triple clamps, but where else should I look to save weight. This is my first year in the Pro MX ranks and I'm already qualified in two classes for regionals for Loretta's and am looking forward to obtaining an AMA Pro license to race the end of this season in the Outdoor Nationals. I was looking into the big bore kit from Pro Action where they go up 80 thousandths on the piston and port and polish the cylinder. They are sponsoring me and doing my suspension right now, so any advice to reasonably increase or make improvements on my bike would be greatly appreciated since you sound very knowledgeable. How did you get your bike down to 235lb for example. My email is javelinmxer@hotmail.com and all information is greatly appreciated.




On your way to racing pro? Good for you!!

So here's the deal.

At the moment, my bike is not the best example of what would make the best pro racing machine. Ya see, there's a big difference between doing something that has results, and doing something that wins races.

The 235 lbs is nothing more than a result. Real engineering is putting a bike together that weighs less, but losses the weight in the most important places.

My bike is just a collection of miscellaneous hack jobs that shaved off a few pounds.

For racing pro, you'll want to formulate a design strategy, (highest yield for lowest lap times) which resides within your budget.

With that aside your priority in areas for losing weight should be 1. unsprung weight, 2. top weight, then lastly, 3. the remaining areas.

Now before I go too far into this whole thing, understand that the greatest contribution to fast lap times is a proper suspension and power delivery for each condition. Even if your bike weights 220lbs, you'll get nowhere if your rear wheel is spinning and/or your tires (and you) are thrashing about. That's a different post - but my point is to not have you make the mistake by mis-directing you into thinking that shaving bike weight, or adding power, is the secret to winning races.

With that in mind, there's a lot of over-engineering on this bike that doesn't need to be there for special applications. However, durability can be compromised.

From here we can either talk about what the ultimate design would be, or I can just ramble about what I did and you can add to your list as you see fit.

In either case, it doesn't take a rocket scientist to see what stuff the factory guys have removed from their bikes that you may still have on yours. Close examination of magazine and Internet photos are a great starting point.

Let's start with that, if not I'll send over a list and you can pick and choose.


Dave J

Great report. Have you looked into changing the rear brake master cylinder? I would like to get rid of the current design for one like the Honda. I heard DB products was developing one. Do you are anyone have any info?

SkinS F


Thank you so much for your insight on the wet sump kit. It always helps to get outside point of views on things especially from customers using our products. I will have Doug read you comments and see what we can do to improve the instructions and the kit. I feel that you have very good points and I am sure we will be able to address them.

Please let me know if you have other comments about the kit that you did not express on TT. I would love to hear all of them.

Thanks for your support of our company and our products :)

Gina Dubach


I also did a wet sump conversion on my 426 motors, but my kits were from Pro-Circuit. I believe that I went thru some of the same problems as you did,only I had more problems. The motor blockoff plates that were sent to me, are junk!! There is no way to ensure that they will stay in place, they just don't fit. I made some new ones, and last week Gina Dubach agreedto sell me some of their parts to improve my kit. pro-circuit says to put 1000cc of oil in the motor. I am going to install the site window in my motors, and I'll let you know if 1000cc of oil can be seen in the window. Dave

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