Montesa Ignition Timing Chart

This is the most complete list that I could assemble. If you have any specs that are missing or see mistakes, I would be greatful if you emailed me. john@rmmontesa.com			# Models with CDI * Models with lighting coils
Model Number	Bike Name	Degrees BTDC	Inch/mm BTDC	Bore/Stroke
3M*	Impala Sport	25	.138"/3.5mm	60.9x60
4M*	Impala	23	.118"/3mm	60.9x60
5M*	Microscoter 60	?	?	38x43
6M*	Comando 175	23	.118"/3mm	60.9x60
7M*	Montesa 50	?	?	38x43
8M*	Kenya	23	.118"/3mm	60.9x60
9M*	Comando Impala	?	?	60.9x60
10M*	Cota 25	22	.097"/2.5mm	38x43
10M*	Cota 25A	22	.097"/2.5mm	38x43
11M*	250 Trial	23	.118"/3mm	72.5x60
12M*	Texas	22	.118"/3mm	60.9x60
13M	Impala Cross 175	25	.138"/3.5mm	60.9x60
13M	Cappra 175 (Italian Model)	25	.138"/3.5mm	60.9x60
13M	Impala Cross 250	32,36 xx	?	72.5x60
?	El Diablo (U.S. model)	?	?	?
14M*	175 Enduro	25	.138"/3.5mm	60.9x60
15M*	Sport 250	27	.157"/4mm	72.5x60
16M*	Cota 74, Trail	20	.157"/4mm	42x54
17M*	Ciclo Montesa 50	?	?	38x43
17M*	Indiana 1st & 2nd Version	?	?	38x43
18M*	Cappra 125 MX	27	.157"/4mm	51.5x60
19M*	172 Cota	24.3	.157"/4mm	60.9x54
20M*	Cota 49	?	?	38x43
21M0001*	Cota 247MK-I	21-27	.098"/2.5mm - .157"/4mm	72.5x60
21M3000*	Cota 247MK-II	21-27	.098"/2.5mm -.157"/4mm	72.5x60
21M6100*	Cota 247MK-III	21-27	.098"/2.5mm -.157"/4mm	72.5x60
21M13830*	Cota 247 Trail	21-27	.098"/2.5mm -.157"/4mm	72.5x60
21M19228*	Cota 247 Ulf Karlson	21-27	.098"/2.5mm -.157"/4mm	72.5x60
21M21482*	Cota 247T	21-27	.098"/2.5mm -.157"/4mm	72.5x60
21M25132*	Cota 247C	?	?	71x60
21M25307*	Cota 247 (1978)	?	?	71x60
21M51001*	Cota 248	?	?	69x64
23M	La Cross	33	.118"/3mm	72.5x60
24M*	Scorpion	27	.157/4mm	72.5x60
25M*	Impala 250 (USA)	27	.157"/4mm	72.5x60
26M	Enduro 75L	24	?	42x54
27M*	Mini	?	?	38x43
28M*	Cota 123, 123T	24.3	.157"/4mm	54x54
29M*	Cota 200	20	.079"/2mm	54x64
30M0001*	Scorpion 50	?	?	38x43
30M5301*	Scorpion 50R	?	?	38x43
31M	Cota TT	?	?	72.5x60
32M*	Cota 80	?	?	?
33M	Cappra 250	27	.157"/4mm	72.5x60
34M*#	King Scorpion	27	.157"/4mm	72.5x60
36M	Cappra 360-GP	23.5	.175"/4.5mm	78x73.5
37M*	Biro 50	?	?	38x43
38M0001#	Cappra 125 VA	?	.059"/1.5mm	54x54
38M1265#	Cappra 125 VB	?	?	54x54
38M2052#	Cappra 125 VB (1978)	?	?	54x54
38M2477#	Cappra 125 VE	?	?	?
38M2878#	Cappra 125 VF	?	?	?
39M*	Cota 242	?	.079"/2mm	71x60
39M*	Cota 304	?	?	71x60
40M*	Rapita 50	?	?	38x43
41M*	Rapita 50	?	?	38x43
41M*	125 Impala II	25.3	.118"/3mm	60.9x60
42M*	Crono 75	20	?	42x54
43M0001	Cappra 250-Five	23.5	.157"/4mm	72.5x60
43M0310	Cappra 250-Five	23.5	.157"/4mm	72.5x60
44M#*	King Scorpion Automix	22	.118"/3mm	70x64
45M#*	Rapita	22	.118"/3mm	70x64
46M0001	Cappra 360-GP	23.5	.157"/4mm	78x73.5
46M0600	Cappra 360-GP/DS	23.5	.157"/4mm	78x73.5
48M*	125 Enduro, Enduro L	20	.079/2mm	54x54
51M0001#	Cota 348	17.3	.071"/1.8mm	78x64
51M49001#	Cota 349 Trail	17.3	.071"/1.8mm	78x64
51M54301#	Cota 348 Trail (1982)	17.3	.071"/1.8mm	78x64
51M15709#	Cota 349	?	.085"/2.1mm	83.4x64
51M20920#	Cota 349 (1981)	?	.085"/2.1mm	83.4x64
51M24524#	Cota 349/4	?	.085"/2.1mm	83.4x64
51M26497#	Cota 350	?	.105/2.7mm	83.4x64
52M*#	Crono 125	?	?	54x54
53M	Cappra 250 GP	27	.157"/4mm	72.5x64
54M0001*#	Enduro 250	22	.157"/4mm	70x64
54M66001*#	Enduro 250A	20	.098"/2.5mm	70x64
54*#	Enduro H, Enduro 250K	20	.098"/2.5mm	70x64
54*#	Enduro 250-H6, 250-H7	22	?	70x64
55M*#	Crono 350	?	?	83.4x64
57M#	Fura	?	?	38x43
58M	Enduro 125H	?	?	54x54
61M00001*#	Coda 330	?	?	83.4x60
61M01500*#	Cota 335	?	?	83.4x60
62M*#	Enduro 75 H6/79, 80 H7	?	?	42x54
63M*	Cappra 250 MX	23	.118"/3mm	72.5x60
66M0001*	Cappra 360 VA	24	.118"/3mm	83.5x64
66M0501*	Cappra 360 VB	22	.118"/3mm	83.5x64
66M1383*	Cappra 360 VB/78	22	.118"/3mm	83.5x64
66M01799*	Cappra 414 VE	?	.118"/3mm	88x68
66M02262*	Cappra 414 VF	?	.118"/3mm	88x68
66M02575*	Cappra 414 VE	?	.118"/3mm	88x68
67M0001*#	Enduro 360-H6	?	?	83.4x64
67M04609*#	Enduro 360-H6/79	?	?	83.4x64
67M7001*#	Enduro 360-H7ET	?	?	83.4x64
67M*#	Enduro 360-H7L	?	?	83.4x64
68M0001*#	Enduro 125 H6/79	?	?	54x54
68M01305*#	Enduro 125 H7	?	?	54x54
73M5001*	Cappra VR	24	.118"/3mm	70x64
73M6001*	Cappra VR	24	.118"/3mm	70x64
73M8089*	Cappra VR-75	24	.118"/3mm	70x64
73M9690*	Cappra VA	24	.118"/3mm	70x64
73M10612*	Cappra VB	22	.118"/3mm	70x64
73M11841*	Cappra VB/78	22	.118"/3mm	70x64
73M13468*	Cappra VE 250	22	.118"/3mm	70x64
73M14928*	Cappra VF 250	22	.118"/3mm	70x64
73M15939*	Cappra VG 250	22	.118"/3mm	70x64
MH 123	Montesa Honda 123	?	?	54x54
MH 200	Montesa Honda 200	?	?	54x64
MH 349	Montesa Honda 349	?	?	69x64
?	Cota 307	?	?	71x60
?	Cota 309	?	?	74x60
?	Cota 310	?	?	74x60
?	Cota 311	?	?	74x60
VTDNT01AOM	Evasion	?	?	74x60
VTDNT03900E0	Cota 314 R (1994)	?	?	71x66
VTDNT03900E1	Cota 314 R (1995/96)	?	?	71x66
VTDMT0EA0VE0	Cota 315 R (1997)	?	?	72.2x61
VTDMT03A0VE01518	Cota 315 R (1998)	?	?	72.2x61
VTDMT03A0XE0	Cota 315 R (1999)	?	?	72.2x61
VTDMT03A0YE3	Cota 315 R (2000)	?	?	72.2x61
VTDMT03A01D3	Cota 315 R (2001)	?	?	72.2x61

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Rebuilding Front Suspensions

There are a great number of Montesa motorcycles that use the Betor front suspension from about 1968 to the 1980’s.  This article will cover in detail the early units.  There are a number of tools used in this process.  I will indicate with an (*) the ones that are not needed for simple maintenance.  This process will involve a complete restoration of a poor working or seized unit.

• Common screwdrivers: 1/8”, ¼”, 5/16”blade width
• Internal and external snap ring pliers
• Dead blow hammers: 1 lb. and 5 lb
• Large wrench sockets.  Usually a 1” and 1 1/4” will be all that is necessary
• Sharp cold chisel
• Wire: 1/8” and ¼” about 18” to 24” length
• Scribe/pick
• Grease and grunge solvent
• Substantial bench vise
• Appropriate Allen wrenches.  Normally the choice would be a 6mm or an 8mm
• *Tire iron
• *WD-40
• *Assorted files and abrasive paper
•  Rubber gloves.  Keep the chemicals off your hands
• *Wire wheel/buffer combination
• *Gunk tank
• *Two pound brass hammer
• *Digital Camera.
• *Compressor and air wrench
• *Copy of the exploded illustration of the assembly found in the parts book
• *An aluminum or steel tube or rod about 7/8” in diameter and 2 ½ feet long
• *Taps and Dies

DISASSEMBLY:

DRAIN THE OIL:

If the fork tubes are still in the triple clamps, loosen the fork cap.  Leaving it in clamps is the best way to hold the fork tube.  If the fork tube has been removed and the cap is stuck it will be necessary to either wrap the tube with a rag or install soft jaws in the vise to secure the tube well enough to remove the cap.  This will keep the fork tube from turning when you attempt to loosen the cap.  This should be enough to keep from damaging the chrome.  You may have to use quite a bit of pressure.

1. Remove the dust covers or rubber accordion (rubber) covers (gators).

2. Once the fork tube has been removed from the triple clamps it will be necessary to screw the cap back on about half the way in to preload the fork spring.

Note: Remember the dead blow hammers?  Use them to dislodge reluctant parts.  Never use ball pein or claw hammer for any of this repair work.

3.  If you have a compressor it is fairly easy to shock the Allen cap screw loose and remove it.  If you don’t have one it will be necessary to compress the fork spring by pressing toward the cap screw to increase friction.  The damper rod is connected to the cap screw and will turn if insufficient pressure is applied. 

HAVING TROUBLE?  If it won’t come loose and you temper has risen then find someone with an air compressor and air impact driver.

ALTERNATE METHOD:

Go and find a tire iron that has a screwdriver like end opposite the bent socket end. 

With the cap and spring removed collapse the slide.

Insert the blade end of the tire iron into the tube and engage the slot located at the end of the damper rod. 

You can now remove the cap screw.

Use a snap ring pliers to remove the snap rings from the top of the fork seals and the retaining clip that holds the damper assembly to the fork tube.

Remove the slider from the damper rod/fork tube assembly.  Most assemblies will simply slide apart with little difficulty.

Note:  These can be extremely difficult to remove.  They can be driven out with the aid of the 7/8” rod or tube and a heavy hammer.  A tread release fluid may help with this process.

Now is the time to remove the fork seals from the slider. 

Note:  If you are dealing with a magnesium slider, stop now. You are working on Marzocchi forks.  You are supposed to be working on aluminum Betor forks; remember?  You will chip or crack the edge.  No one will want to weld this damage.  Chewing gum will not work.  You will have to seek a replacement and that is very expensive.

Fold a rag and place it on the edge of the tube.

Use a common screwdriver by inserting the blade under the top seal and levering against the rag.  The top seal will come out more easily then the bottom seal.

Now try removing the lower seal in the same fashion.  It may come out as easily as the top one but if not you will have to move on to another tactic.

If there is worrisome resistance, take your cold chisel and drive it down on the parameter of the seal to cause it to bow.

Now remove in the same manner as the top seal.  By bowing the seal it releases the holding power of the fit.

Place the damper rod on a clean light colored background.  Photograph it.  At least sketch the location of the parts on a paper so you can reassemble it later.  You will forget the way it comes apart if you don’t do this.  I guarantee it.

Clean All parts.  I use a long rod and a wad made from a piece of paper towel to clean the insides of the fork tube.  Various solvents and snake oils can help in removing the contaminates.  WD-40 works well.

Check the fork tubes for straightness.  Straighten or replace before reassembly.

Note:  Many of the forks have a washer that floats free at the bottom of the damper assembly in the slider.  If the internals are contaminated with grungy oil, it will fall out during cleaning.  The cones on the end of the damper rod need to be removed.  It may take a lot of coaxing.  It is a slide fit. 

FORK SEAL INSTALATION:  The Montesa forks take 2 single lip seals per leg.  They need to be installed with the lips pointed down with the open groove side down.

Clamp the fork leg between vise jaws.

Place one seal on the top of the seal channel.

Using the 1 pound dead blow lightly tap the seal flush with the top of the slider lip.

Select the 1 ¼” socket and place it over the seal.

Use the 5 pound dead-blow hammer and strike the socket to drive the seal to the bottom of the channel.

Place the second seal as the first and repeat steps 4 & 5.

Install the retaining clip.

REASSEMBLY:

1. Reassemble the damper assembly following your photo or parts book diagram.
2. Slide damper assembly into bottom of fork tube.
3. Replace internal snap ring to retain damper assembly in fork tube.
4. Insert the fork spring and screw the fork cap on a few threads to provide pressure to the damper rod.
5. Put a little WD-40 on the seal lips.
6. Place washer into slider.
7. Slide fork tube-damper assembly into slider.
8. Install cap screw through washer and into damper and tighten down.
9. Fit dust cover/gator.
10. Install drain screw and gasket.

Note:  Now I digress.  Most of the following steps I perform in a restoration.  If you don’t want to go to this trouble then replace the seals, reassemble, and pour in the required amount and weight of oil.  Reinstall on the motorcycle and go ride it.   I have found that some things I do with a buffer will ease the reassembly of the forks.

RESTORATION STEPS:

1.  Use white rouge on a buffing wheel and buff the chromed fork tubes.  When finished there will be a thin coating of wax on the surface.  This will help ease the fork boots down the tubes and it will make it easy to slide the tubes past the seals and into the slider.

You may have to file, sand, or wire wheel the sliders to remove surface corrosion before buffing.  Determine what will work best and apply sufficient effort to reach this goal.  If you use sandpaper you will need to reduce the grade to 400 or 600 grit before buffing.

2.  Clean all threads and threaded fasteners with appropriate taps and dies.

3.  Replace all broken, lost, or distorted pieces.

4.  Refer to your sketch as to how to reassemble and assemble the damper rod.

 5.  Lubricate the fork seals with oil.  A drop or two of the oil you are going to use will suffice.  I usually use a little WD-40 instead.

6.  Insert the fork tube/damper assembly into the slider.  You did put the spring back in and screwed the cap down a few threads didn’t you?

7.  Replace washer that was removed from the bottom of the fork slider.

8.  Align the damper with the hole in the washer and slider.

9.  Place the retaining Allen bolt into the hole.

10.  Compress the spring to gain pressure and tighten the cap screw.

11.  Reinsert the drain plug with its washer.

12.  Install the fork boot or dust cover.

13.  Remove the fork cap if the hole in the triple clamps is smaller than the cap.

Note:  When you are ready to assemble the fork tube into the triple clamps you should thoroughly clean the area to be clamped of wax residue where the clamps pinch the tube.  Windex is a safe cleaner for this task.  Otherwise you will never get the forks to quit twisting during your ride.  Control will suffer.  The motorcycle will not go where you want it.  Etc. etc. etc.

14.  Fill the forks with correct oil amount and weight.

15.  Replace for cap and tighten.

Back to Rocky Mountain Montesa

Rim Strapping

(Yes the name is Duct Tape.  I am making fun of the word Duct.)

Frequently, too frequently, motorcycle publications mention a way to do away with the wheel rim strap and use duck tape.

No! No! No!

The problem has to do with the spokes and spoke nipples resting against the inner tube.  If not protected, abrasion will eventually wear through the inner tube and give you a flat tire.  The factory uses a rubber rim strap to cover the nipples and spokes and it does a very good job of it.  If you want to reuse a rim strap then check for cracks and rot that would allow it to separate by stretching it by hand.  If it hasn’t broken then it can be reused.  Replacement straps are available from your local motorcycle source and can be replaced for very little cost.

The only disadvantage of a rim strap has to do with occasional slippage when mounting a tire or difficulty in installing rim locks.  When using a rim strap and rim locks, the strap will hold the lock next to the wheel. You must press in the lock toward the inner part of the tire to allow the bead to drop into its correct place.  If you use a rim strap then you must deal with it.

The use of duct tape creates a number of problems dealing mostly with older application.

1. If it is used on a chromed rim it will lift the chrome, create rust and jam up the spoke/nipple fastening.  You will have to cut the spokes off and the rim and spokes must  be discarded. The adhesive does one of two things.  It either becomes gooey or hardens. The goo attacks the chrome and lifts it and then attacks the spoke/nipple joint.  If it is dry it has hardened into a mass that is very difficult to remove.   It can do both over time.
2. On alloy wheels it usually hardens and has to be scraped, cut, or dissolved off.  All methods take an inordinate amount of time and make any spoke repair miserable.  If you are dealing with a vintage dirt motorcycle this can be the difference in enjoying or not enjoying the process.

I have used a separate method that has worked on most of my wheel rebuilds.  I use plastic electrical tape.  It can be purchase in packs of 10 rolls and is relatively inexpensive.  All spokes must be no longer then one thread above the head of the nipple.  If any are too long then they will have to be cut off or ground down.  I start with a clean rim at the valve stem hole and make three passes around the wheel.  The first past is off a little to one side; the second to the other side about even with the edge of the first pass, and the last is down the center.  I have at least 2 layers over all spoke ends.  I use a box cutter to cut open the holes for the valve stem and all rim locks.  This accomplished what the duck tape is intended to do.

There are a few benefits.

1. When removing the tire you are faced with a plastic strap that is much easier to remove.  Usually I can take a box cutter and cut across it and the strap falls away.  I have even used a screwdriver to snap the strap.
2. In the rare instance when the adhesive has fastened itself to the rim it is much easier to remove and the spokes and nipples are rarely locked together.
3. You will have to use new tape every time you remove the tire for wheel maintenance.  Odd!  That’s what you would have to do with the DUCK TAPE.

Note:  When assembling wheels the spoke threads should have a spot of anti-seize put on them.  This helps when retightening spokes

Back to Rocky Mountain Montesa

Cappra Tire Pressures

This seems to be a secret.  There are a number of you that know this secret but there are quite a few that don’t.  I was one that didn’t for a long time. 

I’m a rather large fellow.  I’m talking 250 lbs. plus.  I assumed that I would need a bit more pressure in the tires than were recommended by those that were the more successful racers (read lighter).  I beat myself up for about 25 years.  I built a 1973 VR and proceeded to slip and slide as I had always done and expected the magic of the VR to vault me into a trophy.  It didn’t happen.  No way.  I had been running around 20 to 24 pounds in the front tire and about the same in the rear.  I found myself being passed by better riders that were laying their bike down on the cases in passing me and then disappearing into the dust within a couple of turns.  The straight-a-way speeds were about the same.  It was the cornering speeds I couldn’t attain.  Mud was even worse.  I was slipping, sliding, and falling while being passed by novices racing on trials tires.

Now that I have got your attention, here are the facts.  Montesa provided recommended pressures for there MX bikes.  I started following them.  I found I was hooking up everywhere.  Only my weight was what was keeping me from success.  Well, that wasn’t all.  I’m blind in one eye and a lack of talent fit in there somewhere.

I checked owner’s/parts manuals for VR, 125 MX, 250 GP, LaCross, etc.  On dry and hard ground you put 13 psi in the front tire and 10 psi in the rear.  In muddy conditions and sandy conditions the pressure is 11 psi in the front tire and 8.5 psi in the rear.

There is some additional maintenance that you will have to perform.

Don’t lock the valve stem to the rim with that valve nut.  Snug it up finger tight against the cap.  This allows the tube to slip a little bit and not tear the valve stem causing a flat.

Your tires will creep around the rim.  Usually the rear tire will creep more than the front tire and you will have to adjust this tire more often. 

Add this to your maintenance before each race on the rear tire:

1. Secure the front of the bike.
2. Elevate the motorcycle. 
3. Deflate the rear tire.
4. Loosen the rim locks.
5. Pry the bead off the left side of the tire.
6. Work the tire back where it belongs.  Use of a dilute soapy water solution is helpful.
7. Remount the tire bead.
8. Inflate to about 20 lbs.
9. Tighten rim lock(s).
10. Deflate to 10 psi.

The front tire should have only one rim lock, the rear tire two.  You should figure out how to adjust the front tire on your own. 

If you think that soapy water will just let it slip more easily, it doesn’t.  I’ve tried tire mounting fluids and a mixture of snake oils.  It’s the rim lock that holds the tire, not mounting fluid.

Back to Rocky Mountain Montesa

Rocky Mountain Montesa

My tribute to John Haberbosch

John passed away a year ago. We said him goodbye at the last Montesada, as you could read in this blog. We miss him a lot; his knowledge and friendship are impossible to be replaced. But I noticed that there is something I can do in his memory. His website had some valuable technical information that I decided to include on my own blog in order to preserve it for the Montesa lovers.

In the next days I'll be posting John's articles trying to keep the estructure and feeling of his original Rocky Mountain Montesa.


Rocky Mountain Montesa

Specializing in Vintage Montesa Bikes, Parts and Technical Information

Tech Articles

Suspension & Tires:

Cappra Tire Pressures – This seems to be a secret. There are a number of you that know this secret but there are quite a few that don't. I was one that didn't for a long time.

Rim Strapping – Frequently, too frequently, motorcycle publications mention a way to do away with the wheel rim strap and use duck tape.  No! No! No!

Rebuilding Front Suspensions – There are a great number of Montesa motorcycles that use the Betor front suspension from about 1968 to the 1980’s.  This article will cover in detail the early units.

Ignition & Timing:

Ignition Timing Chart – This is the most complete list that I could assemble of Montesa timing. 

Checking Timing – This article addresses the two reasons that the Motoplat ignition does not create a spark.

How to Set Your Timing – A simple way to time using a piece of bailing wire, an old spark plug, a plastic protractor and a continuity device.

Troubleshooting the Ignition of the COTA 247 – The first thing you should do is change the sparkplug.  If you go all through the following steps and discover it was a fouled plug you will hate yourself.

Spark Plug Heat Range – The confusion is about what are hot plugs and cold plugs. 

Engine & Transmission: 

Flywheel Removal – Step-by-step on removing a Montesa Flywheel.

Loose Needles – This article is to explain a way in dealing with the removal and assembly of this unusual bearing solution by the engineers of Montesa.

Sleeve Nuts – If you are going to take an engine apart it is necessary to deal with these nuts.

Seal Frustration – There are a number of steps that must be done in order for the seal to slip into place when assembling.

Shifting Difficulties – There are occasions when it is necessary to remove the shift mechanism from the engine.

Exhaust Smoke – Your motorcycle may be smoking for one or both of these reasons.

Clutch Maintenance – Most of the clutches used in the vintage era, from 1963 to 1984, used metal to metal clutch plates.  This article will cover these models. 

Clutch Drag Solutions – I have over time found some ways to reduce some or nearly all clutch drag.  There are two approaches to this problem.

Information:

Evolution of Cota 247 – Am important list of changes throughout the life of this great bike. 

Paint Codes – A short list of modern paint codes for Montesa. 

FYI - Origins of Mud Guards  – Some thought on the use of the word "mudguard".

Una Impala 2 vitaminada: El RAL digital programable.

Igual no es lo mejor en términos de técnica literaria empezar un relato por su punto culminante. Pero cuando se agarra un teclado tan contento como estoy yo hoy, se puede hacer cualquier cosa. Así que empiezo por el mejor resumen visual posible del sábado de trabajo con los Vitale sobre mi modesta Impala 2 que nos sirvió de conejillo de indias:

¿Te vale con leer que en 6.000 revoluciones hay dos CV de diferencia entre el encendido con el avance calado a 3mm y la curva que hicimos a medida? Recuerda que estamos hablando de una moto que rinde poquito más de 10 caballos con su carburador de 22 milímetros, su admisión tapada y su motor sin tocar para nada.

Y no sólo es eso, porque se puede hacer otra lectura parecida comparando dos imágenes adicionales:

La primera muestra los 100 kilómetros por hora clavados que entregaba la moto en banco con su encendido de serie al empezar a trabajar sobre una curva especial para ella. La segunda los ¡120 kilómetros por hora! que hacía al final de la jornada.

Sin cambiar nada más que el avance del encendido, y como puedes ver en el gráfico de arriba, se estiraba unas pocas de rpm más que marcaron ésa diferencia. La verdad es que no me lo hubiera creído si no lo veo allí mismo.

Y sí, ya sé que no los veré jamás en la carretera, y menos con mi peso. Pero los 120 del final son perfectamente comparables con los 100 del principio puesto que las condiciones eran exactamente las mismas. Mismo banco, mismo día, misma temperatura, mismo carburador, misma bujía, mismos cuatro chiflados metiendo mano a una pobre Impala 2 en busca del caballo perdido en una mañana de sábado que ahora os cuento.

Porque todo esto parte de que nos habíamos comprometido con Andrés y Víctor a dejarles la primera unidad operativa de nuestro kit de programación de encendidos digitales para que puedan mejorar el rendimiento de sus motos de carreras. Y como eso incluía nuestra necesidad de comprobar sobre el terreno el funcionamiento del cacharro en un banco de potencia, les propusimos tener una jornada de I+D completa, y les pedimos ayuda para desarrollar en su banco una curva específica para mi Impala 2, que pudiera servirnos de punto de partida para el resto de Impalas.

Tened en cuenta que sobre potencia e inventos maravillosos que la mejoran hay más bulos que sobre la vida sexual de Julio Iglesias. Y que el único modo real de comprobar una mejora es poniendo la moto en un banco y midiendo un antes y un después. Ya decía aquel sabio que lo que no puede ser medido no puede ser mejorado.

Así que mi amigo Ramón se montó en su AVE a las 7 de la mañana y a las 9:50 estaba yo en Atocha con la moto en el remolque para irnos a trabajar. Al menos, eso es lo que le decimos a nuestras respectivas mujeres y, de momento, cuela.

Llegamos a casa Vitale y moto al banco para empezar a trabajar: se trataba de tomar una medida del funcionamiento "de serie" en la Impalita, cosa que hicimos sin montar nada de electrónica adicional aún. Y en resultado fueron los 100 km/h que os mostraba antes, y esta curva de potencia:

Era lo esperado. Poco más de 10 caballos a rueda en una moto a la que se suponían unos 10 a salida de cambio. Supongo que en parte el escape Sport Rally que lleva como única modificación, es el responsable del incremento.

Y ahí enchufamos el módulo RAL digital al que programamos dos curvas: una "recta" de 3 mm antes de pms, exactamente igual a la de serie, y otra con la que fuimos tocando valores de avance en busca del mejor comportamiento posible. En las dos fotos de abajo tenéis una de las arrancadas previas a medir, y a los tres sabios mirando la pantalla del portátil y proponiendo ajustes para optimizar el rendimiento ...

... que luego Ramón traducía en puntos de modificación del avance que pintaban y repintaban la curva para adaptarnos a las características del motor. Es lástima no haber hecho capturas de pantalla de la aplicación, porque se usa de un modo enormemente simple y permite hacer muchas cosas: poner un punto de corte, modificar la forma de la curva pinchando sobre ella y arrastrando el ratón, etc.

Como estaba claro que sin modificar alimentación, escape o compresión, las características del motor nos iban a limitar mucho el aumento de potencia máxima, nos centramos en buscar un par lo más lleno posible, trabajando sobre todo por abajo, con un resultado magnífico:

Si os fijáis en todo lo que sucede "a la izquierda", es espectacular. La moto rinde mucho antes la potencia y deja una curva de par mucho más plana que con el encendido calado a 3 mm de pms. Está claro que esos 3 mm son un compromiso, pero no el óptimo en casi ningún momento.

La curva que podéis ver arriba es producto de avances cortísimos en arranque y ralentí, y se dispara hasta 5 mm antes de pms en la parte más alta del recorrido ... que es lo que hace que entregue más potencia más arriba y se estire más.

Ahora falta hacer la prueba del nueve, que es pasar una temporada usando la moto y empleando la facilidad de cambio de curva en caliente que hemos incorporado en esta versión, y que se maneja desde el manilla, como podéis ver abajo:

Porque aunque parezca un disparate, mi moto lleva ahora a la derecha un conmutador adicional con dos botones para el "cambio de mapa" que me permiten dejarla como vino de fábrica o emplear la curva optimizada ... y que cuando lo pongamos a la venta suponemos que usarán para llevar curvas más agresivas o más planas para poder tener dos motores distintos con un solo toque de un dedo.

¿Cómo terminará todo esto? Pues sepa Dios. De momento, con los dos mejores mecánicos de Ossa en España metiendo mano a una pobre Impala 2 sin cortarse un pelo.

Seguiremos informando.

RM Lightning Bi-Campeones de España con Ossa Vitale

Si nos cuentan hace un par de años que íbamos a ser campeones de España con RM Lightning cuando empezamos con este lío, nos hubiéramos partido de risa. Pero lo cierto es que así ha sido: desde aquel Octubre de 2012 en que presentamos la primera unidad operativa en la Montesada, hasta este Septiembre en que Víctor Menéndez ha ganado dos campeonatos de España de Cross de Clásicas en categoría pre-76 han pasado menos de 24 meses.

Realmente, lo que queda por hacer es agradecerles la confianza en nuestro producto, lo mucho que hemos aprendido trabajando con ellos en el desarrollo del encendido programable para competición, y el cariño con que siempre nos han acogido en su casa.

Y como ellos son personas discretas y no presumen de nada, espero que no os importe que lo haga yo. Aquí tenéis el resultado de la última carrera en que la Ossa Vitale con encendido digital programable RM Lightning hizo su vuelta de clasificación más rápida en ¡2,5 segundos menos que la Husqvarna que le seguía!

Víctor, Andrés ... ¡Enhorabuena!