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My 10cts

  • <i class="fa--xf fal fa-check "><svg xmlns="http://www.w3.org/2000/svg" role="img" aria-hidden="true" ><use href="/data/local/icons/light.svg?v=1758297946#check"></use></svg></i> Discussion starter Discussion starter Petrus
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Petrus said:
Received the sidepanels from #1 son yesterday. ingers x-ed they fit.

A week of rain forecasted so not riding = time to faff.
First buy a can of matt black spray paint.
Take the engine covers off, tape off, spray and lay asideto dry,
Take the filter box lid off, drop in the Sprint filter.
Modify the lid.
Put is all back together.
🤞 🤞 🤞




.View attachment 19817
Click to expand...
They look good
 
Slight change of work order; all ready to put back but still need to buy the spray paint :oops:
Time for a cup of coffee and thán go out for that.

As expected one of the bronze inserts unscrewed. Serious PITA that. Put some glue on and screwed it back.
The Sprint fliter has a more generous rubber surround and I have decided that I will not bugger the lid; do without. Was not going to refite the intake harmonicas anyway. Added a droplet of glue in the corners and it will stay put.

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Next episode:

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The blank aluminium preiviously showing through the honeycomb now is matt black thus ´invisible´.
The plate looks befitting to me. Imo less ´IN YOUR FACE´ than the 1800cc.
Still have to start the engine so no info on that yet.
 
Beejeezus :eek:

Ok, I was aware that the intake is the bottle neck but thís bad??!!!

There is supposed to go though 900 cc per beat. For comparisons sake put a 1 l. milk carton next to it.


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No, I am NOT squeezing it. This is how it is fitted. The engine must suck, literally.

I know this is but óne link in the chain but it is the by far weakest one.
The exhaust obviously holds back flow too but there are two factors which make it less critical: The servos actuating the flaps are easily deleted and secondly the exhaust gasses are expélled under pressure. The intake is fed by ambient air pressure only. Any drop in pressure in the inlet tract = drop in BMEP.
 
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After the shock HÁD to roll the bike outside and start.

Obviously, it is tick over and a bit blipping the throttle so not representative for actually riding on the road.
Nevertheless, the difference is quite striking.
Not on the intake. I was a bit surprised about that but giving it a second thought it makes sense as the throttle is just blipped a bit.
Three things:
- When blipping, the torque respoinse it a lot stronger and a mean a lót; holding one hand on the open cover to feel air flow, it is absolutely necessary to put the lnee under the valve cover to compensate for that hand.
- Even just blipping a bit I can feel air going into the honey comb.
- The exhaust note is a lot more agressive. As is to be expected from the increased torque reaction.

For those disappointed by the exhaust note of the lovely vintage pear dops I think this may be the first mod. Well second, first would be flap servo delete.
 
To put it in a different context, the total volume of the air box construction is less than 2 liters.
At full bore at 4k revs the engine thus wants to empty this in 0.03 secs., every 0.03 secs.
This illustrates how fast the ambient air pressure needs to supply demand; how critical the path between the outside of the bike and the engine side of the air filter is.
 
Red64 said:
Nicely done. Looks very nice
Click to expand...

Thanks and I am quite sure that it greatly improves breathing and will add extra oomph because the wideband will add the extra fuel to the extra air.

On a side note, I saw that the harmonnica rubbers got rather dusty. This points at a small flow getting in from the top opening, surpassing the gills/harmonica restriction. This also explains the holes in the filter box lid.
I suspect that the top opening is a necessary ´evil´ for the engine support plus cables and that rather than put a rubber seal surround up there, they made use of this bit of ´false´ air.
As such this confirms that there is no issue with the covers being open. In fact I suspect this was the original intention: Machining the openings in de aluminium casings costs money.

p.s, I am flabbergasted by the lack of knowledge/understanding and resulting denial/rejection of the workings of the R18 motor management system in some circles (not here).
I have been personally insulted even! Well, attemot to that were made. Cannot be bothered if the swine don´t like pearls 😅

The air mass sensor senses the amount of air going in and sends input to the ECU. The wideband O2 sensor measures the exhaust gas composition and again sends input to the ECU. The ECU plots that into the programmed charts and adjusts the amount of fuel needed to keep the mixture within factory specifications.
The values of the program have quite a widen band width meaning the ECU cn cope with a wide variance of conditions.
This is not just theory; it has been confirmed by the bench tests Roland Sands did for their two R18 project bikes. They concluded that the standard tables have 20-25% margin. Hence they achieved 110 hp with the standard program.

The much mentioned ´repro´ consists of changing the parameters/values the ECU seeks to maintain.
On an otherwise unmodified bike it wil result in a different compromise in how the engine runs. It is very much akin to the Rock/Roll/RAin modes although thóse maintain the factory mixture values whereas a repro might but does not nééd to.
I have little to no doubt that the repro will do the same as above because it remains the same program; it is ´only´ maintaining changed values.
So yes the Brentune will still have the same results, again just more (y)

Lastly I am NOT writing that the R18 nééds more oompf. Actually I write that for me it has enough. I just do not like an egine to literally suck and the R18 is an extreme case because the huge pots are literally throtteld to meed noise regulations ánd because the wide band O2 sensor allows the ECU to adjust.

Rant over.
 
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Back to sidecars for the moment. Still no top speed testing weather.

Fitting a sidecar to the R18 is going to cost 7k up.
Buying an EFi Ural sidecar 2WD outfit will cost me 10k.

The former will also loose me the solo bike, the latter will gain me 2WD and between lies hassle vs ready to roll.
 
Nice day tody. Forecasted too so planned to go for a nice extended spin, drink/east something at the beach and on the way back test top speed.
We geared up, rolled the R18 outside and nope, nothing. Well, the red bbq grill. Waved the key fob, moved all switches, in/out gear etc but just a red light.
So dressed lighter and went with the car, taking the manual with me.
To make doubly sure it is not the voltage, put the charger on the jump connections. Should not be the issue as it was over half but... best be sure.

Comfie at the beach went through the manual which made me nóne the wiser.

Back up, disconnected the battery and tried again. Same result.
Hey... moving the fob about I díd get a response.
So, after the check up routine, pulled the clutch and pressed ´start´ upon which all went black.
Retried, same result.
Hûh :oops:

Don´t know why but with all checked, switched to reverse and that was indeed indicated. Pushed statrt and....IT STARTED. But, but, but,....
Put it out of reverse. Kept running.
Switched off retried starting. All went darl instantly again.

Turns out it is overly sensitive of the reverse lever position.
Be that as it is, it still does not solve the invisible fob thing.

With ´compound´ weird problems one gets nervous about a ground issue....

With the print/book/etc,. shop at 50 meters have replaced the CR2023. For all of 1.5€ I bought piece of mind.
Obviously tried and the electronics ´sees´ the fob aok.
 
Again ccccóld weather. All stayed frozen in the shade yesterday so no-go for the R18.
Today above zero but wind and mist. Weird combination but that is the mountains for you.
The máy be a nicer window tomorrow. Hope so because thereafter again a cold front with SNÓW :eek: forecasted from 200 meters altitude. We are at 650...
As such rather bored and thus ordered 🫣😇 a metal oil cooler guard on Ali-express.
 
and now while on the subject of being bored and ALi-express, what about a sump guard? Seems a good idea with a plastic sump and low ground clearance. Anyone fitted it?

https://es.aliexpress.com/item/1005...722-5f6c-46bb-b2c7-4071113505b7-0&pdp_ext_f={"order"%3A"12"%2C"spu_best_type"%3A"service"%2C"eval"%3A"1"%2C"fromPage"%3A"search"%7D&pdp_npi=6%40dis%21EUR%2129.20%2118.69%21%21%2133.48%2121.43%21%402103890917672661816935866e1fc4%2112000044820198144%21sea%21ES%217030950466%21X%211%210%21n_tag%3A-29911%3Bd%3Ad262082b%3Bm03_new_user%3A-29895&curPageLogUid=b4gXIxy2Ice2&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A1005008389147225%7C_p_origin_prod%3A
 
Today another window in the weather forecasted and laterin the afternoon the sun indeed came out for about 2 hrs before going down.
Donned my gear, rolled the bike out and again all black when pushing the start butto after the safety routine.
Sigh...
With the dash lit selected more, went through the menu, re-selected ´roll´ and now it did start. Weird.
Anyway, rumbled off.
It immediately feels more punchy. Even while just warming up.

Warmed up it eats the puddin´ 😅
How much more is obviously only anecdotal but it growls notably louder on both ends and hits harder to the point of almost scarily so: It pulls hárd.
Top speed it the same at about 195 (GPS 187) indicated but now I felt the soft limiter coming in as the engine was still pulling.
Before opening up the intake it was alreay impressive how it pulls but in third it is now fringe scary. It really is a literally strong difference.
Apart from the weird electronical thing, I am a happy puppy.

For me it has shown that the air entry is the bottle neck. Not the filter but the entry to it.
The filter surface is rather small for the engine capacity so a less restrictive one does make sense but only if the air can flow in.

Lastly the self tuning of this set up means that more air in is actually more power.

About the latter, it feels good to have more punch but the bike in NO WAY needs it and the 180-185 km/h top speed is apart from illegal* totally senseless.

* apart from sections of the IoM mountain circuit and ever less stretches of autobahn.
 
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Btw both did the IoM and the Autobahn 🫣 The latter highly overrated as it is just a highway, the former can NOT be overrated as it is an anachronism. Started out as a reliability trial of early nineteenhundred´s motorbikes, grew out of all perspective. Despite all the youtube reels, there is nóthing that can prepare you for the real thing.
37.7 miles course and not only did BMW see it as their most notable historic success, the M1000RR holds the current 136 mph lap record.

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That as side note.

Meanwhile véry curious for someone else going this surprisingly easytune route and reading the experience/opinion.

Was looking at the weights of the various models again. The total weight of the sidecar combo I would still like to build is the same as that of the TC.
 
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Today (y) weather. Sunny but chilly; just above zero. Good for a ride if careful with not thawed out road in the shade.

Charming thinks the engine is more powerful. Even lost her grip on my jacket at one time :oops:

She guestimates 10-15% more effort to hold on but especially way more immediately she says.

It is obviously not the extra horses but the more direct extra torque does need more attention. The throttle response is instant now.
 
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Petrus, I think another member asked this but I didn't see a reply... is there any possibility you, or your son, would be willing to share the file for printing the side/air intake covers? Or perhaps offer some covers for sale, like the UK creator of the original Tobinators for the R1150GS did, years ago? Your posts are very informative and I'm curious to experiment with decreasing air intake restrictions.

Cu Dubh
 
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It made no sense sell the hide before the bear was killed:
My son will be very happy to print some more.
He will do them in his own time though as he does need to pass exams.

Do you lot think 20€ ex. shipping ok for the first sets?
They are a straight fit.
The development and test prints were/are on me as Í wanted them for myself.
Any gains are for him.

Shipping will be cheap as they fit in envelop and are lightweight.
As I am not a business will ship as ´free sample 3D print motorcycle part´.

Please do note that the intake rubber nééd be deleted for it to be effective.
Next better is delete the lid.
Final is fit a sports filter. I found a frame to keep the filter in place superfluous. Just add a bit of glue/silicon for extra measure. Remember it is sucked ín so inclined to stay put.
Without the rubber and the lid but stock filter it will still be effective.

To be continued.
 
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