The Hodaka Club Forum

Just wanted to see what the consensus is on motors with the oil injection feed. I would like to see if it works on my 01 when I get things put back together, but even if it does am I better off just using premix? If it doesn't work or I just decide to use a premix what do I use to block the pump off without ruining it? Have those pumps had a good history or being reliable?

I’m guessing you will get lots of opinions for both. I like the convenience of oil injection and having many injection bikes over the past 40 years I have never had a failure. But on the other hand I understand the the argument in favor of using premix such as nothing to go wrong, knowing exactly what your mix is...
My $.02

Here's the advice from a real Hodaka expert and supertuner (Hodaka Dave). He recommends leaving the oil injection system in place. The context for this advice is regarding a 250ED motor he is boring for me. I plan on using the bike for hare scrambles/enduros. The advantage associated with running the oil injection system is that the fuel/oil mixture the engine sees is based on engine RPMs - the higher the revs, the greater the oil enrichment. In the race setting my ED will be used in, there will be substantial relatively low-rev operation so the higher fuel to oil ratio at low revs will reduce the likelihood of oil fouling of the spark plug at low revs. On my only other dedicated race bike with oil injection ('74 TM125), the oil injector has been removed. That bike operates continuously in the 4,000-8,000 RPM range so for that, I want dependable, consistent oil delivery. The Mikuni oil pumps used in Hodaka engines are famously dependable. For an 01 used for trail riding, the oil injection system is advisable according to Hodaka Dave. The one caveat I would add is to include confirmation of oil injector pump operation and adjustment as part of your routine maintenance program.

Thanks guys, that's is good info! The 01 I plan on riding a bit more and trying some trial stuff so it will see more action then the rat in that department. I guess my plan is to make sure it works correctly and go from there. Appreciate the feedback. It seemed like previous post were anti pump.

I believe oil injection is a really good deal for normal riders. If the machine is not tuned properly, you still have more oil delivered at the higher RPM range. To me a fine tuned race machine, is not going to oil foul a plug. To me there are people racing for fun and those racing to win. So if you have auto lube, do you need to modify it to use premix for racing, not at all. If you want to race, do you need to start with a oil injected engine, not at all. The advice as given above is correct, some folks have never ridden a fine tuned machine, the limp goose can be turned into a tiger. --------------- Clarence

I should also add that in the TM, I'm running 105 octane race gas premixed 20:1 with racing castor. To my knowledge, no one makes an injectable racing castor.

These oil pumps are easy to check. I used to pull the banjo fitting from the intake and put a 6mm bolt in the hole. You can drain your tank, very easy with the petcock so exposed, and put in a quart of premix. Start the engine with the oil line in a pop bottle or other clear container. You can pull on the cable at the adjuster or work the pump arm manually with the cover off to speed things up. No need to sit and over rev the engine while looking for results. A fast idle will work. Dont expect oil to be shooting across the room. At idle the flow is almost zero, that why I rotate the pump arm or pull the cable to get enough flow to even show. Hard to believe the engine can survive with this tiny trickle of oil, but they do. You can also pull the oil lines of at the pump and add a piece of clear hose, but the original lines are usually hardened right onto the banjo fittings. Leaving the hose with their tiny clamps alone is usually the best option.

Good advice here.

Check to be sure it's pumping IF your concerned that it isn't.

Check that the cable is adjusted "correctly". There's a spec somewhere. I don't have a Hodaka with oil injection, but someone on this forum must have the instructions for this & might post it for you.

These Mikuni pumps are a cylinder & piston device, gear driven. There are no seaIs I see that can cause any problem with delivery. Oil may leak out of the pump, but it should keep on pumping.

I'm a bit aways from testing the pump but I will check back in on the thread when I do. Thanks for the tips. Do they seem to smoke less then bikes that aren't oil injected?

What you need to be SUPER careful with are some of the older Suzuki and Kawasaki Motorcycles. The Oil Injector Systems DIRECTLY fed the Left side Crank Main Bearing and would also (spray) feed the lower rod bearing. Blendzall Ultra Castor is advertised for Oil Injector Systems BUT I would cold test it in a refrigerator to make sure it still pours out of the bottle. I found it comical to see the top Pro MX Racers holding a bottle of (Not Castor) oil in the Magazines but when they flew by at Glen Helen ALL you smelt was Maxima 927 or Blendzall Green! Joe Ormonde.

Maxima 927 here. I'm pretty sure it is not compatible with oil injection nor would I want to try it.