[nitro.1000bhp]

On this recent trip to Leh we had 3 impulses, 2 with Zma engines and 1 with the stock engine... the difference in performance was quite obvious. Where the impulse would struggle to climb inclines in 1st gear the Zma engined ones could climb it with ease in 2nd and 3rd. Cruising was effortless with 95Kph coming in about 6K Rpms and the impulse's stock suspension was more than capable enough to soak up what ever the streets of Ladakh had to throw at it.

I think the problem with the stock impulse engine is more cos of the gearbox than its lack of power..it has a really short 1st gear and an extremely tall 2nd. The clowns @ Hero need to be blamed for this as I am pretty sure Honda might have had a different GB setup for the bike. May be they cheaped out or just assumed that they had the brains to figure it out.

Overall I'd say that it was money well spent...For those who wanted to know if the Zma engine can be transplanted, well the proof is in the pudding (pics above of the blue bike) It can defenitely be done and it simply transforms the bike into something instantly more usable and much more a fun machine that never fails to widen that grin.

(Mods done are : Renthal 3/8 CR high Hand bars, MSR Hand guards, Polisport front fender, custom aluminium skid plate and custom header & exhaust.)

[niks_devil666]

What is the typical cost of a zma engine and total cost of the mod job? What did you do with the impulse engine afterwards?

[nitro.1000bhp]

Originally Posted by niks_devil666

What is the typical cost of a zma engine and total cost of the mod job? What did you do with the impulse engine afterwards?

The engine cost me 15K with 10K Kms on the odo, 9K for the exhaust incl. stainless steel end can. Labour charges another 10K so a total of around 35K for the whole job. I still have the impulse engine but I dont have any plans for it at the moment.

[man_of_steel]

Originally Posted by nitro.1000bhp

On this recent trip to Leh we had 3 impulses, 2 with Zma engines and 1 with the stock engine... the difference in performance was quite obvious. Where the impulse would struggle to climb inclines in 1st gear the Zma engined ones could climb it with ease in 2nd and 3rd. Cruising was effortless with 95Kph coming in about 6K Rpms and the impulse's stock suspension was more than capable enough to soak up what ever the streets of Ladakh had to throw at it.

I think the problem with the stock impulse engine is more cos of the gearbox than its lack of power..it has a really short 1st gear and an extremely tall 2nd. The clowns @ Hero need to be blamed for this as I am pretty sure Honda might have had a different GB setup for the bike. May be they cheaped out or just assumed that they had the brains to figure it out.

Overall I'd say that it was money well spent...For those who wanted to know if the Zma engine can be transplanted, well the proof is in the pudding (pics above of the blue bike) It can defenitely be done and it simply transforms the bike into something instantly more usable and much more a fun machine that never fails to widen that grin.

(Mods done are : Renthal 3/8 CR high Hand bars, MSR Hand guards, Polisport front fender, custom aluminium skid plate and custom header & exhaust.)

Amazing bike Nitro. I was always an impulse fan. But I've always felt a >=200cc engine would make it an awesome dual purpose. the ZMA'a unit in it is absolutely perfect! And regarding the super short first gear, I think that is a boon for such a bike with a 150cc motor so that it can go over any gradient/obstacle with the first cog! A taller first gear would have made it a nightmare on the gradients!

I wanted to know a couple of things.

As the change in engine would require change in the RC book as well, will it be easy to get approval from the RT Office for this engine swap job?

Also is the engine transplant a direct bolt on job? How is the frame handling the added weight and power?

[nitro.1000bhp]

Originally Posted by man_of_steel

Amazing bike Nitro. I was always an impulse fan. But I've always felt a >=200cc engine would make it an awesome dual purpose. the ZMA'a unit in it is absolutely perfect! And regarding the super short first gear, I think that is a boon for such a bike with a 150cc motor so that it can go over any gradient/obstacle with the first cog! A taller first gear would have made it a nightmare on the gradients!

I wanted to know a couple of things.

As the change in engine would require change in the RC book as well, will it be easy to get approval from the RT Office for this engine swap job?

Also is the engine transplant a direct bolt on job? How is the frame handling the added weight and power?

Thank you, yes the 230 definitely does some justice to the bike's capabilities. Once a dull, strangled bike is now full of life, happy doing wheelies and powerslides at much lower Rpms. And because we are using such low Rpms we were actually getting a better average than the 150 which was screaming everywhere.


The problem with the gear box is the transition from 1st to 2nd gear actually. When you shift to 2nd after wringing in 1st it just doesn't do much or stalls if you are on a steep incline, so you have to come back to 1st and repeat the process.

I haven't given much thought to rto formalities..I still have the old engine so I could get it back to stock if I ever plan to sell it.

The rear mounts of the engine is a direct fit, the front ones need machining or you could make one from scratch in a lathe.

Attaching some videos from the trp

http://www.youtube.com/watch?v=UzEgb_Am_QQ

http://www.youtube.com/watch?v=Fcqif50LiHI

cheers.

[am1m]

Originally Posted by ringoism

Better as a solo tourer, obviously, but the bike never failed to impress fellow riders on Bullet 350s (who said more than once they wished they were riding something like my machine instead of theirs).

You said it man! I've done Ladakh on my Bullet and I'd love to do it again, but on a much lighter bike. The Bull is awesome, oodles of torque, but a real pain on that kind of terrain.

Originally Posted by nitro.1000bhp

Where the impulse would struggle to climb inclines in 1st gear the Zma engined ones could climb it with ease in 2nd and 3rd.

Hmmm, so it would be fair to assume that a stock Impulse with a pillion would really struggle up there and probably not make it?

Great engine mod job with your Impulse man, but I just don't have the know-how to carry out something like that myself.

Darn it Hero Motor Co., just come out with a company kitted ZMA-engined Impulse would you?!

[man_of_steel]

Apparently, read a report not so long ago that Hero Motorcorp is developing a new 250cc motor. It would be great if that motor would make it to the Impulse!

[ringoism]

Originally Posted by nitro.1000bhp

I think the problem with the stock impulse engine is more cos of the gearbox than its lack of power..it has a really short 1st gear and an extremely tall 2nd. The clowns @ Hero need to be blamed for this as I am pretty sure Honda might have had a different GB setup for the bike.

I felt the same thing both times I test rode one (with pillion) on some steep link roads near the (Mandi, H.P.) showroom. As indicated, screaming in 1st or bogging down in 2nd. On flat roads, it felt responsive and powerful enough... but then, our intended use is not flat roads!!!

Sometimes it's a little tricky to get gearing just right on a dual-sport bike, since it's expected to do extremely diverse duties well, with only 5 or 6 ratios to work with. My DR350 (Suzuki - kept abroad) has really, really close ratios, such that with it geared up decently for 100kph use, even with 30bhp it struggles to start out on steep grades in 1st.

The ZMR transplant really seems an appropriate upgrade, apart from legal concerns. Low-end torque is the key to multi-purpose machines, and it comes with displacement.

Short of that, I'm assuming the CBZextreme has closer 1-2 ratios, and if so, perhaps (with the basic engines presumably being identical) changing the 1st & 2nd gearsets in the 'box would improve matters for the average rider, while avoiding any potential legal issues. Though as another commented, the general lack of power could make a taller 1st gear a little tricky at the worst off-road points.

With the ex-showroom Impulse prices seeming to have actually dropped since last year (71,400 up here in H.P. currently - I suspect they're not selling too great) and the dollar high, I'm on the verge of buying one... but am hoping I won't regret it.

The aforementioned 500 Classic rider (fellow 60kph club member), is just crazy about the Impulse. Obviously no 500, but among 150cc bikes, he feels it's the best in terms of responsiveness & power (he also owns a Unicorn commuter, which he says is simply no comparison). Also a lot less vibes than the 500 (obviously)!! His mechanic in Mumbai is an ex-moto-crosser who also owns one and is allegedly pretty satisfied with it.

It seems to me that an aptly-tuned and geared 150 should be capable of decent performance. I rode an FZ (with pillion) a lot in the Mizoram hills and though it didn't have such broad torque-spread as a 200+cc might, it was plenty strong without winding it out, so long as you didn't mind working the gears a bit (though of course you're not running into altitude-related power losses there). I tackled some extremely steep grades on little back city lanes (in Aizawl) solo without any difficulty. FZ's have 14.1bhp, I think, vs. the Hero's 13.4. Traditional tuning methods (pipe, carb, maybe a little more compression ratio) should be able to net another 10%...

-Eric

[ringoism]

Originally Posted by nitro.1000bhp

Thank you, yes the 230 definitely does some justice to the bike's capabilities. Once a dull, strangled bike is now full of life, happy doing wheelies and powerslides at much lower Rpms. And because we are using such low Rpms we were actually getting a better average than the 150 which was screaming everywhere.

The videos are absolutely inspiring. The bike is obviously running well in the hands of a capable rider. I need no further convincing re: the usefulness of the bigger engine, and it's such a shame that Hero didn't do it themselves; If Bajaj could offer a water-cooled Pulsar 200 for sub-Rs90,000, Hero should certainly be able to get a more appropriately-sized air-cooled powerplant into the Impulse for around the same. If they'd have done it from the start, I think they'd have captured a lot of sales this past year that instead went to R-E. Adventure touring seems to have come of age in India (as indicated by the bike traffic in the beginning of the second video). My fear that Hero would finally do it AFTER I bought the 150 is one reason I've been hesitating.

I remember the Tso-Moriri route well, and seeing it again makes me want to get back (my wife seems up for doing it on two bikes - but we're gonna have to wait for these babies to grow up a little!).


Many Thanks,
-Eric

[n_aditya]

Originally Posted by nitro.1000bhp

For those who wanted to know if the Zma engine can be transplanted, well the proof is in the pudding (pics above of the blue bike) It can defenitely be done and it simply transforms the bike into something instantly more usable and much more a fun machine that never fails to widen that grin.

Thanks Nitro. I've been curious about the engine transplant and glad to read that it can be done and add's much needed punch to the bike.

However, please clarify if you retained the stock gearbox or did you have to change/modify that as well, to accommodate the bigger engine.

Also, how easy is it to get the new engine number endorsed in the RC book to avoid any legal hassles?

[nitro.1000bhp]

Originally Posted by ringoism

The videos are absolutely inspiring. The bike is obviously running well in the hands of a capable rider................................ ..............................................but we're gonna have to wait for these babies to grow up a little!).


Many Thanks,
-Eric

Thank you Eric, I glad the videos have inspired you and even your wife to get out and ride.

Its no surprise that hero goofed up the R&D bit on this bike, drawing comparisons with bajaj is a crime, they jumped on the r&d bandwagon a long while ago while hero was still caught happily napping selling rebadged commuters for the masses. The quality of the bike, overall is simply appauling right from the switch gear to every single rusted nut and bolt. My brand new bike infact had a horribly bent front rim but instead of getting the service guys to fix it shoddily I got them fixed using my local mechanic.

The 250 LC thats apparently doing the tests is going into another ZMR like bike and not the impulse. So I suggest you dont get your hopes up on that.

Also thanks for the bit on the extreme's 1st and 2nd cogs. I shall get my friend to test it as he was sorely missing the driveability in these two cogs.

I am posting a few more videos for your viewing pleasure Enjoy.

http://www.youtube.com/watch?v=qpi8axQHS7w

http://www.youtube.com/watch?v=XciyQb3oRgs

http://www.youtube.com/watch?v=l0p9bJ1lGZ0

Cheers mate and good luck

[nitro.1000bhp]

Originally Posted by n_aditya

Thanks Nitro. I've been curious about the engine transplant and glad to read that it can be done and add's much needed punch to the bike.

However, please clarify if you retained the stock gearbox or did you have to change/modify that as well, to accommodate the bigger engine.

Also, how easy is it to get the new engine number endorsed in the RC book to avoid any legal hassles?

Hi, the engine is a stock karizma engine with stock everything except the exhaust. Although the left side case cover will need some shaving to get itself accommodated in the frame. Other than that there are no clearance issues, everything bolts right into place.

I haven't really enquired about RTO formalities yet. I still have the old (new) engine and if I ever plan on selling the bike I can simply swap it and sell the zma engine separately. May be the jeep guys can throw some light on the matter as I see many with swapped engines. (JEEPSTERS PLEASE HELP!).

[ringoism]

Originally Posted by nitro.1000bhp

the difference in performance was quite obvious. Where the impulse would struggle to climb inclines in 1st gear the Zma engined ones could climb it with ease in 2nd and 3rd.

I think the problem with the stock impulse engine is more cos of the gearbox than its lack of power..it has a really short 1st gear and an extremely tall 2nd. The clowns @ Hero need to be blamed for this as I am pretty sure Honda might have had a different GB setup for the bike. May be they cheaped out or just assumed that they had the brains to figure it out.

Apart from odd gearing, I'm also kind of wondering why exactly the Impulse has to be quite as much as 30kg heavier than something like the foreign-market Honda CRF150f which is pretty much an adult-sized frame. Despite having the same basic engine (identical bore/stroke and similar power output even), reviewers seem to think it has plenty of performance, at least at lower speeds. 30kg overweight on a 150cc bike is no joke. Wonder what (if anything) could be taken off / exchanged to improve matters there for the Impulse (aluminum wheels for the steel ones might be a good start).

Cash in hand, was planning to go buy the bike tomorrow. Pretty dismayed to hear your negative comments on the quality (rusted bolts, switchgear, etc). Sure doesn't seem to be the Hero Honda of early Splendor days (which I know could do 1lakh km before a rebuild). As I said, hope I'm not going to regret this... but tired of trying (in absence of genuine spares, and with quality control issues of its own) to get my old KB125 (with off-road modified suspension) running as it should - it's been a fun machine and taken me all over the Himalayas - but it's making me deaf and vibe-ing me to death lately. I swore the last time I tore into its innards that it was going to be the last time...

If we want perfection, we can only look upward...

-Eric

[ringoism]

Moderator. Sorry (again) double posts keep going out for some reason... I won't let it happen again. :-)

[ringoism]

Originally Posted by nitro.1000bhp

Labour charges another 10K so a total of around 35K for the whole job. I still have the impulse engine but I dont have any plans for it at the moment.

The only technical question I had re: the ZMA swap (not found online info) was the electrical connections; I was assuming the CDI unit itself would probably be different, but do the actual connectors (i.e., from engine (incl. charging coil(s), neutral switch, etc) mate up directly to the Impulse harness, or did you have to have some custom re-wiring done?

The rest of the work I could handle easily enough myself (I'm one of those hands-on type mechanical engineers and have decent tools at my disposal also).

Heard from one more local rider today (who sometimes borrows one from its lady owner to ride between Kullu and Manali) dissatisfaction with the stock bike's power, so am going to delay my purchase till I can borrow it myself and do a more extensive solo test ride (Tuesday, hopefully).

My plan: If under my normal riding conditions it seems close - but not quite - I'll go ahead and buy one and figure I can pick up acceptable power later with a free-flow silencer, airbox mods, an overbore / thinner head gasket (compression ratio is 9.1:1 here, and 9.5:1 abroad), and careful carb tuning. And I'll see what I can toss out to lighten it a bit (I do have a 21" aluminum front rim I could fit, for one thing, and the leg/sari guards would definitely be heading for the kabbad.

If it's not close at all, well: 1) ZMA swap; 2) wait and see if Hero does a 225 themselves; 3) do a RX135 up with Unicorn mono-swingarm (one local mechanic did a clean job of it a few years back) and my killer imported Suzuki enduro front forks and that 21" wheel, and be ready for anything. I know the 135's can get 40-50kpl., they can be seriously quick / responsive, and are very light / nimble (besides having a bit more practical (for kids and tank bags) flatter tank and seat. Just was really hoping to avoid another re-engineering project... (Please Hero, do consider a 225 Impulse at below Rs85,000 - people will be lining up at the showrooms, and RE's domination of the adventure touring market will be finally crippled).

Thanks,
Eric