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Jelly

1127F engine running hot

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As you might know, I run a Katana (#1) with an 1127F motor in it. There is an oilcooler of a B12 mounted for the nessecary cooling. At first when built last year, the bike was OK and running 90 degrees, in warm weather slightly hotter. But suddenly temperatures went up and I now have developed a cooling problem. Btw, all temps are measured with a simple oil-plug meter, so not accurate but it gives an idea. 

The first thing noticed was that a part of the Blandit cooler was flattened (strange, as I didn't do it myself, maybe some kind of vandalism when parked somewhere), which means that a part of the cooler doesn't have air flowing through. But I cannot imagine that this would have such effect that the bike now runs 120-140 degrees and in traffic/city even higher. 

Pulled the sump out today:

 17506113_1615087068508664_1297697215_n.jpg.e07622946af1b227a493853a32681ced.jpg

Looks quite clean, and it seems that the pressure regulators all function as should. 

The oil coming from the motor didn't have any debris in it and was even not that black (as I only did around 3-4000km with it max). When draining the oilcooler and filter, oil was coming from both in and outlet so there's no blocking there.

Does anyone have a clue? Maybe @Rene EFE could insert a photo of the blocked oilcooler but I don't reckon thats an issue too (there is a HEL cooler on standby for replacement, but would rather use that on my ET). 

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Oil coolers can withstand quite a bit of flattening/blocking.  My Manx Grand Prix/TT bike's cooler is a right mank but it didn't overheat to the point you could smell it. 

You haven't got a blocked jet or something have you causing it to run lean and hotter ?

 

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It's running really hot, not only readings from the tempmeter but also heat coming from the engine, higher idling, etc. the meter's just there for the indication.

also noticed that when removing the exhaust the middle two pipes were quite white on the inside...

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your focus is on the means to get rid of the heat  - I would check your oil filter and oil pressure to see if the relief valve is working - stuck open ?

other focus is something has changed that creates heat - previous comment ref: blocked jet, or an air leak around the carb manifolds, or has the ignition timing gone out, or is there a blockage in the ex pipe - if you happen to be using adjustable cam sprockets - have they slipped

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Engine is fully stock and came from a known-good bike. I'm quite stumped by the issue because for the moment, there's nothing pointing at the real problem. 

I vote to change the sump, to take that out of the equation. I'll snap a pic of the cooler later.

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Pulling carbs apart tomorrow, and going to check the plugs and drain the tank. Previous owner and builder has had several problems with fueling, it might have something to do with the modified tank then? Although the last time I rode it a couple of weeks ago it was smoking like a dutchman... (no pancakes were harmed)

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Hmm.. Just had a look, cilinder 2 -3 were running quite lean indeed. Don't think the cooler is the problem, I run the dragbike without cooler and sometimes take it for a spin around the village as you know ;) no problems with temperature. 

Check oil pressure to be sure, put the needles of carburator 2 -3 one step higher/richer to be sure they don't run lean. But first change the sump indeed incl regulator as the engine get very hot and you can touch the cooler.

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Setting the needles a bit higher was also what the Dyno man said last year, but I can't remember doing this (I do think we did). Also, bike was sometimes 'sneezing' from it's exhaust, which sounded like a misfire. 

In my defense, the bike was actually built in 3,5 days last year so the engine was more or less chucked in :P But what is strange, is that it ran perfectly in the previous owners bike with the same setup.

Anyway, report tonight when @Rene EFE and I are going to search for the fault(s). 

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3 hours ago, Jelly said:

but I can't remember doing this (I do think we did).

We're Dutch; stuff tends to get hazy :pimp:

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The sneezing can be a result of a cilinder running lean. Could be a dirty nozzle. You got a infrared temp meter? Then you can measure the temp of the exhaust pipes and read what the bike is doing, quite handy in these cases.

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I do have an infrared tempmeter, but as the engine is dismantled now... Not going to build up and measure. This has been something which was there from the beginning. Starting to suspect the carbs more and more... 

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Well, pulled the plugs from the engine, white... As @Rene EFE mentioned, if we did this with a 2-stroke the engine was already far gone. Removed the fuel tank and the fuel filter which is in line. The inner filter bit was loose in the filter which won't help when the engine is requesting petrol via vacuum. The (aftermarket) breather on the tank works, but as the previous builder had a lot of fueling problems with his turbo build I assume the current state of the tank won't help. 

The 34mm F carbs are quite dirty... But most of the dirt is on the outside. 

carb1.jpg.bcad328eab334d0afab8bd853ca912ab.jpg

What I did notice is that all the emulsion tubes were a bit loose... As you can see: 

carb2.jpg.3ce75b1e029b7a10bc576192d6cd4f7d.jpgcarb3.JPG.04c567ae3aa2edd91e580d5c84c8a18a.JPG

Which is probably caused by using Dynojet jets instead of Mikuni jets. They're smaller and won't hold the emulsion tube in place (see above pic). This made me think. After I had the bike on the Dyno last year with @bruteforce I swapped the jets from 140 Mikuni to 132 Dynojet (equivalent 125 Mikuni) as the bike was running too rich. We gave it a good run afterwards on the dyno and then I started using it. The engine issues were building up, but I did at least a good 3000km on it. 

 

dynajetchart.jpg.66189fb361067101dfbfc731c0c40357.jpg

We decided as the carbs are that dirty, and running on separate K&N podfilters as nothing was available when we were building it (with a small timeframe) to change the carbs to one of the sets of 38's (are they?) we had laying around:

carb4.JPG.510ae44ccd2be0bb51698f51447b62fc.JPG

Changed the inletrubbers, ordered some Ram Air filters which will be mounted with original Slingshot airboxrubbers. 

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If the emulsion tubes are loose, there must be a problem with the fitment of the mains. In my 34mm carbs there were brass rivets under the mains to make sure the tubes were "pulled" down into place. The bike ran fine before, why change a winning team if they're only dirty? I can get them ultrasonically cleaned for little money, no problem.

 

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There was a problem with the fitment. These rivets waren't in place anymore. I missed it when mounting the Dynojet jets. But when I want to refit I can fit Mikuni's of the same size as there are a couple available in our stock. 

The 34'ers need to be ultrasonic cleaned, that's a sure thing. I just want to try to see how it runs with other carbs. If it doesn't work, will convert back to the 34'ers and in the mean time I can get them cleaned. 

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Defo Mikuni ,34,s are good  carbs , those mikuni jet spacers are very important to hold the emulsion tubes Down, hence your lean issues and hotness problem ! You can just make them from alloy tube really there just a spacer .

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I will certainly not chuck them in the bin. But because I have 2 sets of 38's Mikuni in the house which look quite clean and neat, just going to try them. Together with Ram air filters on original airbox mounts. Probably will ask @bruteforce to give the 34's to his ultrasonic cleaning guy....

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Did a fair bit of work on the motor yesterday with @Rene EFE. Sump fitted again, surgically cleaned (but there was no debris in it). And it fits even better than the last time (no sweating/leaking). Decided to use the 34's instead of the 38's as they were completely different from my other set of 38's (BST38SS), for which I have a kit with new needles and emulsiontubes etc. Went for a different main, instead of the 132 dyno jet, a 130 Mikuni big jet so it tightens the emulsion tube in place. Needles in the one to last bottom groove of the needle. Fitted the exhaust and fired the bike up with a bit of fuel. Started instantly and sounded much more healthy than before. Let it run and everything seemed good. But cil 1/2 were flooding with petrol, so that needs a bit of research, again, the carbs... We'll see if we can get it properly running with these carbs in this state. I do want to ultrasone them but first I need to buy an ultrasone cleaner (or send them out). 

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Just fit new float needle valves in and this will fix flooding issues, only need untrasonc cleaning if there is idle issues, I can happily say I've used the German made profi fuel max . Additive in tank it's amazing stuff and ONLY one I'd would recommend . Cleans jets float bowls inside like new £15 per bottle lasts ages . 

M&p in uk sell it and sure you can find it in Europe too.

 

image.jpeg

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16 minutes ago, Jelly said:

Good to know! How do you remove the floaters from 34's? They seem to be fixed to the carb... I cannot get to the float needle valves.

they sell it here: https://www.mpartz.nl/profi-fuel-max-270ml-carburateur-reiniger-p-22535?

will order some this week

Ofcourse you can. There are aluminum pins that go through the hinge of the float. There's a visible flat one one side. Use a steel pin (drijver) on the other side to gently tap the pin out.

I have my 34mm turbo carbs for sale, they have had all new float seats and needles last year....

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Brute force is right, Just use tiny drill bit or tiny tack or nail tip to tap float. Hinge pin out, be gentle mind you as the hinge posts can break if your too hammer happy, 

 

 

image.jpeg

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I didn't use bruteforce to drive the pins out... :D but thanks, will have a look and @bruteforce you have a message regarding your carbs...

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Well, that escalated quickly. Bought @bruteforce his carbs as he converted his bike to EFI. :) 

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