Performance and torque.

[Louis Horn]

As I’ve mentioned before, I just bought an Alp 650 but has not ridden it yet. I previously posted the question of pushing up the power.

I have since spoken to a number of people and got all sorts of advice. The trick is to make sense of everything. Who knows what he is talking about and who’s just talking nonsense? Not easy.

Here is what I assumed to make most sense and when I get home is what I’ll do.

Based on my own knowledge of motorcycles over the last 20 years I listed the things that made sense.

• Drill holes in air box lid for breathing. (the standard air inlet hose is a bit small)
• Use Pipercross, K&N or similar low resistance air filter.
• Do away with the PAIR system and blank off holes.
• Free flow exhaust, big pipes front to back, losing cat, sub chamber and collector.
• Good spark plugs and leads (what brand or grade is best for 650?)
• Full synthetic oil for maximum protection. (Prevents carbon buildup under rings.)
• Smoothing out and polishing the carb bore.
• Smooth out all ports and edges both inlet and exhaust ports.
• Regular service.
• Make sure the air fuel mixture is 100% correct.
• Make sure the slide position is correct. (needle is fixed)
• Throttle position sensor, advance 3 deg for 95 Oct and keep same for 93 octane.
• Check Fuel lines and fuel filters.
• Then balance carbs.

The next step up is a big bore kit and I won’t go that far. I spoke to my local Honda dealer and he can do these mods.

Is there anything on this list that should not be done and if so, what are the reasons and pitfalls?

[edteamslr]

Just ride the thing and stop worrying about 10/10ths performance on a 5/10th bike - it's then that you'll realise that these things are not about 'performance' per se. More about "enabling" you to enjoy more riding.

Drill holes in air box lid for breathing. (the standard air inlet hose is a bit small) NOPE
Use Pipercross, K&N or similar low resistance air filter. YES, a washable one perhaps.
Do away with the PAIR system and blank off holes. NOPE
Free flow exhaust, big pipes front to back, losing cat, sub chamber and collector. END CAN WILL SUFFICE but jetting may need changing.
Good spark plugs and leads (what brand or grade is best for 650?) NOPE
Full synthetic oil for maximum protection. (Prevents carbon buildup under rings.) NO DIFFERENCE (FULLY/SEMI - change it to service intervals and leave it alone)
Smoothing out and polishing the carb bore. NOPE
Smooth out all ports and edges both inlet and exhaust ports. NOPE
Regular service. YES YES
Make sure the air fuel mixture is 100% correct. NOPE
Make sure the slide position is correct. (needle is fixed) NOPE
Throttle position sensor, advance 3 deg for 95 Oct and keep same for 93 octane. NOPE
Check Fuel lines and fuel filters. AS PER SERVICING
Then balance carbs. YES.

SA is a dusty place, wash or change your airfilter regularly. Most of your changes just won't be felt. Most of your changes take time and money and just won't be felt on your bike. Buy a motocrosser or a racebike with the money you save and tinker with that instead.

[oggy]

Is there anything on this list that should not be done and if so, what are the reasons and pitfalls?

Er yes - all of the above, as you should go any buy the 700 instead. Far easier and cheaper than all the mods you suggest.

[oggy]

Is there anything on this list that should not be done and if so, what are the reasons and pitfalls?

Er yes .. all of the above. Suggets you purchase/swap for a 700 instead - far cheaper and easier than all the mods you suggest.

[Louis Horn]

Ed, you are the second person to suggest this. I already have an after market end can on and the Honda dealer did the jetting for this.

My concern is this. I bought the bike in a fantastic condition from a friend. The bike is amazing and he loves it. We used to ride together and as long as he is one up, all was fine. When he loads the wife, boxes and tank bag packing for the weekend, power became a problem. Me and my other half is a bit heavier. I bought the bike as a trail tourer and a second (midsize perfect for her) bike for her to ride on road. It cruses comfortably at 80 mph, but as soon as you need to pas or overtake a vehicle, there is very little reserve power.

I will take it for 2 trips before I do anything and see how it goes. Some one said the Africatwin motor fits in the same frame. Is this true?

The cost not a concern. I will spend the money if it makes a difference. I’m hesitant of the 700. Is there a big difference in power? I like the concept of no ABS or fuel injection on the 650. If I could get a 10% power gain, it would be the absolute perfect bike for why I bought it.

[Louis Horn]

Is there anything on this list that should not be done and if so, what are the reasons and pitfalls?

Er yes .. all of the above. Suggets you purchase/swap for a 700 instead - far cheaper and easier than all the mods you suggest.

I don’t really like the 700, prefer the no ABS, carb and larger front wheel. Just need 10% more power.

[steveR]

regular service

IMO, without a doubt, the most important one of your list...

I was quite surprised at how sharp my 'alp was after a 16K service this week. A real zip to the throttle response.

I had not thought it amiss at all during the run to Normandy a fortnight or so ago and was getting 50mpg two up and FULLY laden and while unhappy at high speed cos of the overloading, it was happy to bimble up to 90 on an overtake.

About the only thing I would like to do now, is get a Hagon shock as the hassle in adjusting the rear shock is a real PITA... Anyone got one spare??? I am too mean to buy a new one as I am putting the dosh to a late Summer trip....

[wheeliebin]

I'd hold off on your plans for the time being, wait until you've ridden the bike for a while and have a feel for it.

I think there are massive inconsistenties from the manufacturing process, rear wheel horsepower varies from 43 - 49bhp, fuel consumption varies from 43 - 57 mpg, some owners report a flat spot at around 4,000rpm and some don't, some bikes suffer poor running at altitudes and some don't.

You never know, you may have a good one which doesn't need any mods.

[Louis Horn]

I'd hold off on your plans for the time being, wait until you've ridden the bike for a while and have a feel for it.

I think there are massive inconsistenties from the manufacturing process, rear wheel horsepower varies from 43 - 49bhp, fuel consumption varies from 43 - 57 mpg, some owners report a flat spot at around 4,000rpm and some don't, some bikes suffer poor running at altitudes and some don't.

You never know, you may have a good one which doesn't need any mods.

Very wise words. That’s probably what I’ll do. I must admit I am a bit spoilt with power. Riding big torque bikes most of my life and before that Motocross type bikes. I will just have to get used to it first and then decide. Good advice, thanx man.

Louis.